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Definition
| How a single cell becomes multicellular |
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Definition
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Definition
| Everything in the embryo is preformed and got bigger as it developed (ex: theory of homunculus hidden in every sperm) |
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Definition
| New structures arose progressively. New structures arise by progressing through a number of different stages. |
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Definition
| Theory devised by Schleiden and Schwann which states that organisms are composed of cells, the basic unit of life, and multicellular composites arise from a single cell, so development must be epigenesis |
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Definition
| Weismann. Offspring do not inherit characteristics from the body (soma) of the parent but from the germ cells (Egg and sperm) |
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Term
| 6 processes needed for development |
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Definition
| 1. Cell division 2. Cell differentiation 3. Pattern formation 4. Morphogenesis 5. Growth 6. Apoptosis |
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| The mouth is always on the _____ side |
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Definition
| Most terminal part of the animal region (upper part of the egg) of the egg, where the nucleus resides and usually away from the yolk. In Xenopus the pigmented animal half is called the animal cap. Animal pole is more animated and has more movement. |
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Definition
| The terminal part of the vegetal region of an amphibian egg, and is directly opposite the animal pole. The lower region, usually contains the yolk, and is the region from which the endoderm will develop. |
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Definition
| Mitotic division without cell growth so successive cleavages the cells become smaller and the volume remains constant while surface area increases. |
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Definition
| Stage in development that is the outcome of cleavage (12 division cycles). The blastula is a hollow ball of cells, composed of an epithelial layer of small cells enclosing a fluid-filled cavity |
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Definition
| Fluid filled cavity that develops in the interior of the blastula |
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Definition
| The slit-like invagination on the surface of amphibian embryos where the mesoderm and endoderm move inside the embryo at gastrulation. |
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Definition
| Dramatic cell movements, endoderm and mesoderm move to the inside of the embryo, ectoderm on the outside |
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Definition
| The mesoderm gives rise to a rod-like structures that runs from head to tail and lies centrally beneath the future nervous system |
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Definition
| Blocks of mesoderm on either side of the notochord which will give rise to the muscles and vertebral column as well as the dermis of the skin |
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Definition
| Ectoderm above the notochord folds to form a neural tube which gives rise to the spinal chord and brain |
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Definition
| In vertebrate embryos is a stiff rod like cellular structures that runs form head to tail and lies centrally beneath the future central nervous system. It is derived from mesoderm. |
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Definition
| Structure, formed from ectoderm above the notochord which folds in, and will eventually give rise to the spinal cord and brain. |
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Definition
| Depends upon interactions between parts of the development embryo and can result in causing different tissues (cell to cell communication). Environment can influence! |
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| Depends on specific determinants on the zygote that is transferred to one of the daughter cells (asymmetric division) and the developmental fate is inherent and environment cannot influence. |
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Definition
| Destroyed one cell of a two celled embryo and resulted in _ a frog embryo so he concluded the development is based on a mosaic mech and that the living cell had its character and fate determined at each cleavage. He was wrong because it didn't separate the cells |
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Definition
| Experiment with a sea urchin where he separated cells at two cell stage and resulted in death of one, and the surviving cell developed into a small but normal larvae |
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Definition
| Ability of the embryo to develop normally even when some portions are removed or rearranged |
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Definition
| The process where one tissue directs the development of another tissue (Spemann organizer and the twinned embryo) |
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Definition
| Dorsal lip of the blastopore, which forms where gastrulation begins on the dorsal surface of the amphibian embryo. Needed for the development of the AP axis and the DV axis and induction of the nervous system from ectoderm |
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Definition
| Describes what they will normally develop into. BY marking cells in the embryo a fate map of embryonic regions can be constructed. Having a particular fate does not imply that a cell could not develop differently if placed in a different environment |
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Definition
| The germ layer that gives rise to the gut and associated organs such as the lungs and liver in vertebrates |
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Definition
| The germ layer that gives rise to the epidermis and nervous system |
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Definition
| Germ layer that gives rise to the skeleton-muscular system, connective tissues, the blood, and internal organs such as the kidney and heart |
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Definition
| Implies a stable change in the internal state of a cell such that its fate is now fixed, or committed. A determined cell will follow that fate when grafted into other regions of the embryo. |
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Definition
| When isolated in a neutral environment they develop to their normal fate |
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Definition
| A cell is said to be competent if it can respond to the inductive signal. Such as having the correct receptors or transcription factors needed for gene activation |
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Definition
| The process by which one group of cells change the fate of another group of cells. 3 forms of cell-cell induction: 1. Secreted diffusible molecule 2. Surface molecule (membrane bound receptors and ligands 3. Gap junctions (channels) |
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Definition
| Any substance that varies in concentration and directs different fates at different concentrations |
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Definition
| One cell inhibits its neighbors from adapting a similar fate. Occurs when developing structures produce an inhibitor that prevents the formation of any similar structures in the area adjacent to them and therefore the structure becomes evenly spaced |
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Term
| Asymmetrical cell divisions |
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Definition
| Cell divisions in which the daughter cells are different from each other because some cytoplasmic determinants have been distributed unequally between them (central to Wiseman |
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Definition
| Development depends upon progressive series of instructions |
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Definition
| Stage at which the embryos possess a distinct head, neural tube, and somites, and at which embryos of the different vertebrate groups closely resemble each other |
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Definition
| Post-cleavage embryo composed of a solid layer of cells (rather than a spherical blastula (as in chick, zebra fish, drosophila) |
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Definition
| Other word for chick blastoderm |
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Definition
| Stage in animal development that is the outcome of cleave. The blastula is a hollow ball of cells, posed of an epithelial layer of small cells enclosing a fluid-filled cavity (blastocoel) |
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Definition
| Signaling center on the dorsal side of eth early xenopus embryo. Forms in the dorsal vegetal region of the blastula as a result of cortical rotation Specifies the Spemann organizer above it |
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Definition
| Condensation of cells at the anterior end of the primitive streak in chick and mouse embryos. Corresponds to the Spemann organizer in amphibians. Cells of the node give rise toe pre-chordal plate and the notochord in chick embryos and the notochord in mammals. |
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Definition
| In avian and mammalian embryos the node is the embryonic organizing center analogous to the Spemann organizer of amphibians. |
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Definition
| Crescent shaped region of small cells lying at the front of the posterior marginal zone in the chick blastoderm |
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Term
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Definition
| Primitive streak of the chick and mouse embryo is the site of gastrulation and the forerunner of the A-P axis. It is a strip of ingressing cells that extends into the epiblast from the posterior margin. Epiblast cells move through the streak into the interior of the embryo to form mesoderm and endoderm. |
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Term
| Difference between frog and chick gastrulation |
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Definition
| Chick has proliferation and growth of cells |
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Definition
| Early mesoderm marker (notochord) |
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Definition
| Stage of mammalian embryo corresponds in form toe h blastula stage of other animals and is the stage at which the embryo implants in the uterine wall |
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Definition
| The very early stage in a mammalian embryo when cleavage has resulted in a solid ball of cells |
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Term
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Definition
| At 8 cell stage blastomeres increase the area of cell surface in contact with each other |
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Definition
| Cell with many nuclei in a common cytoplasm. Cell walls do not develop during nuclear division within the very early Drosophila embryo and this gives rise to the syncytial blastoderm in which the nuclei are arranged around the periphery of the embryo. |
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Term
| Key difference in drosophila development |
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Definition
| First divisions are only nuclear divisions and it is replicating DNA and not undergoing cytokinesis |
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Definition
| Name given to the ventral blastoderm of the early drosophila embryo, from which most of the embryo will eventually develop |
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Definition
| Sheets of prospective epithelial cells derived from the cellular blastoderm in the larvae of drosophila and other insects which at metamorphosis give rise to adults structures such as wings legs antennae. Usually 40 cells ea. Grow during larval development and form foleded sacs of epithelia to increase surface area. |
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Definition
| Specializations in the cuticle secreted by the epidermis used for traction |
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Definition
| Independent developmental units that give rise to the segments of the larvae and adult (drosophila) |
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Term
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Definition
| Pax 6 in humans and eyeless (if) in flies |
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Definition
| One of the variant forms of a genetic locus differencing from other forms in its nucleotide sequence |
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Definition
| Caused by mutations int eh gene dystophin (X linked recessive). Dystrophin gene encodes a large protein that is part of a complex that anchors the skeleton to the muscle |
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Term
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Definition
| A hypomorph mutation (eg truncated product with some function) |
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Term
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Definition
| Amorph or null (eg complete loss of the dystrophin) |
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Term
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Definition
| One copy of the gene is not sufficient to produce enough activity for normal development |
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Term
| Dominant gain of function mutations |
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Definition
| These are dominant mutations in non haplo-insufficient genes (hyper-morph anti-morph, neo-morph) |
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Term
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Definition
| Complete loss of gene function (Deletion/early stop codon) |
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Definition
| Partial loss of function. Sometimes referred to as leaky mutation (ex: temperature sensitive mutant) |
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Term
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Definition
| An increase in wt gene activity (protein is more active/stable/made in greater amounts) |
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Term
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Definition
| Dominant negative. A decrease in wt gene activity. Always dominant. Poison product |
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Definition
| A new function of a gene. For example mutations that cause the gne to be expressed at different times or in different tissues during development such as ectopic expression (antennpedia) |
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Term
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Definition
| Generating animals that have cells composed of at least two different genotypes |
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Definition
| Some genes act many times during development |
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Definition
| Gene only affects the cell the gene is expressed in |
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Definition
| Developmental process that proceeds whens without the requirement of extracellular signals to be continuously present |
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Term
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Definition
| Cortex 5um beneath membrane rotates 30 degrees driven by microbules towards the site of sperm entry. Crucial for giving dorsal side regional identity and leads to the formation of a signaling center in the vegetal region called the Nieuwkopp center |
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Term
| DV axis of xeno determined by? |
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Definition
| Determined by site of sperm entry |
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Term
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Definition
| ~earlier version of Spemann that manifests itself in explant experiments. Sets the initial dorsal ventral polarity |
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Term
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Definition
| Dual role as a gene reg. protein and a protein that links cell adhesion molecules to the cytoskeleton |
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Term
| AP axis of the chick defined by? |
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Definition
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Term
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Definition
| Of the chick embryo is a dense region of cells at the edge of the blastoderm that will give rise to the primitive streak. PMZ specifies the ventral end of the DV axis. |
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Term
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Definition
| A member of the TGF-B superfamily, coded for by the gdf-8 gene which inhibits muscle mass formation and knockouts lead to super strong mice, babies and bulls |
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Term
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Definition
| Mutation that affects motor protein dynein and blocks mvt of cilia which results in 50% show situs inversus and respiratory problems |
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Term
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Definition
| Encodes left/right dynein motor protein (mice with mutated iv gene have hearts that loop left 50% of the time) |
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Term
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Definition
| Vegetal cells induce the animal cap cells to make mesoderm |
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Definition
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Term
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Definition
| Transcription from zygotic genes begins and cell cycles become asynchronous, triggered by the ratio of DNA: cytoplasm |
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Term
| Evidence for at least two signals of mesoderm induction |
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Definition
| If you culture dorsal mesoderm with animal cap cells you get notochord and muscle, if you culture ventral mesoderm with animal cap cells you get blood and connective tissue |
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Term
| Evidence for the 3rd mesoderm inducing signal |
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Definition
| The Spemann and Mangold transplantation of the organizer to the ventral marginal zone induced a new dorsal axis |
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Term
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Definition
| Functions both as a transcriptional co activator and as one of the proteins present at cell junctions. In its role as a transcriptional co-activator it is activated in early development as a result of a wnt signaling pathway |
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Term
| Candidates for Spemann O inducer? |
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Definition
| NOGGIN! And chordin and frizbee |
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Term
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Definition
| A protein made uniformly in the Xeno blastula which promotes ventralization of en embryo, inhibited by dorsalizing factors chordin and noggin |
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Term
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Definition
| Protein made in the prospective mesoderm which promotes ventralization of the embryo and is inhibited by the dorsalizing factor frizbee |
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Term
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Definition
| TF involved in Spemann O specification |
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Term
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Definition
| TF involved in mesoderm induction |
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Term
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Definition
| Candidate genes to induce ectoderm to become epidermal |
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Term
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Definition
| A 60 aa helix turn helix DNA binding motif TF |
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Term
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Definition
| 180 base pairs that encode the homeo domain |
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Term
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Definition
| Family of evolutionary conserved genes and a family of homeobox containing genes that are present in all animals and involved in the patterning of the AP axis. Combinatorial expression characterizes different regions and structures along the axis and these position specific combos are called hox code |
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Term
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Definition
| Maternal gene involved in the development of the drosophila AP axis. Initially mRNA is localized to the anterior end of the embryo, where it inhibits caudal translation and activates transcription of zygotic hunchback |
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Term
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Definition
| Maternal gene involved in the development of the drosophila AP axis. Initially the mRNA is localized in the posterior of the embryo where it represses hunchback |
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Term
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Definition
| Maternal gene involved in the development of the dros. AP axis. Initially mRNA is localized all over the embryo, but bicoid protein represses its translation in the anterior. (specifies posterior) |
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Term
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Definition
| Maternal & later zygotic gene involved in the development of the dros. AP axis. Initially present all over the embryo, zygotic transcription activated by bicoid in the anterior whereas it is inhibited by nanos in the posterior |
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Term
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Definition
| Maternal gene product codes for a RTK receptor, which is uniformly distributed but only activated at the poles because that is where the trunk ligand is processed. Needed for terminal specification |
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Term
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Definition
| Maternal gene product codes for a Ligand for torso, secreted all over but only processes at the poles |
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Term
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Definition
| Maternal gene codes for a protein which is processed in the perivitelline space after fertilization on the ventral half of the embryo and activates the toll receptor which leads to high conc. of dorsal protein in ventral nuclei (V:D gradient) |
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Term
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Definition
| Maternal protein present throughout the cell membrane of the fertilized egg but is preferentially activated on the ventral side of the embryo by the spatzle fragment and leads to high conc. of dorsal protein in ventral nuclei (V:D gradient) |
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Term
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Definition
| Inhibitor of dorsal, when spatzle binds the toll receptor on the ventral side of the embryo this activates the tube adaptor protein which activates the pelle kinase that phosphorylates the cactus inhibitory protein and leads to its degradation so dorsal can enter the nucleus and activate gene transcription. |
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Definition
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Term
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Definition
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Term
| What is the toll pathway used for in humans? |
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Definition
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Term
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Definition
| Surround the developing oocyte in drosophila and synthesize proteins and RNAs that are to be deposited in it |
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Term
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Definition
| Somatic cells that surround the oocyte and nurse cells during egg development |
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Term
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Definition
| Maternal mRNA which codes for a gene that is involved in specification of the AP axis and DV axis of the dros. embryo. Signals to the torpedo receptor on follicle cells and inhibits the production of pipe |
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Term
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Definition
| Maternal gene localized to posterior needed for pole cells (germline formation) |
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Term
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Definition
| Zygotic gene in drosophila (secreted) DV patterning, needed for neuroectoderm to develop (inhibits dpp) high levels in ventral region (analogous to chordin) |
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Term
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Definition
| Dpp. Zygotic gene in drosophila (secreted) DV patterning high levels in the dorsal region. (analogous to BMP4) |
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Term
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Definition
| Zygotic gap gene that codes for a transcription factor which functions to localize pair rule gene expression |
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Term
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Definition
| Zygotic gap gene that codes for a transcription factor which functions to localize pair rule gene expression(represses the eve gene and sets the posterior border of Eve stripe 2) |
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Term
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Definition
| Zygotic gap gene that codes for a transcription factor which functions to localize pair rule gene expression |
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Term
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Definition
| Zygotic gap gene that codes for a transcription factor which functions to localize pair rule gene expression (represses the eve gene and sets the anterior border of Eve stripe 2) |
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Term
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Definition
| Zygotic gap gene that codes for a transcription factor which functions to localize pair rule gene expression |
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Term
| Krupple expression in a bicoid mutant |
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Definition
| Broader stripe because maternal hunchback is still expressed at a level which can activate kruppel |
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Term
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Definition
| Of the drosophila embryo is the extra-embryonic membrane on the dorsal side of the embryo |
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Term
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Definition
| Zygotic segmentation (segment polarity) gene, homeodomain TF which defines the anterior region of the para-segment and the posterior region of the segment (sets up a boundary of cell lineage restriction) |
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Term
| Mutations in segment polarity genes cause |
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Definition
| Defects in AP segment polarity like mirror image or tandem duplications of the A or P parts |
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Term
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Definition
| zygotic gene product codes for a secreted/membrane protein which acts as a ligand on the patched receptor, inhibits the smoothened receptor, releases the protein CI (cubitus interruptrus) to go into the nucleus and activate the transcription of en, dpp, and wingless |
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Term
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Definition
| Transforms the anterior compartment of the haltere into an anterior wing region |
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Term
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Definition
| Transofmrs the posterior compartment of the hatlere into a posterior wing region |
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Term
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Definition
| complexes of RNA and protein that become localized to the posterior end of the fertilized egg of c. elegans |
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Term
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Definition
| when a group of cells leave the tumour and invade surrounding tissues and migrate to new places to set up a new tumour |
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Term
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Definition
| The first oncogene discovered, too much of this gene (hyper-morph) leads to much cell proliferation which can cause cancer. |
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Term
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Definition
| An antibody targeted on to the HER2 receptor on the cell membrane. Used as a drug to treat breast cancer in which cohere is overactive HER2 receptor (sometimes due to duplicated HER2 genes). |
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Term
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Definition
| the coding together of the sides of the embryo on the ventral side of the body to form the gut |
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Term
| Dorsal epidermal intercalation |
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Definition
| A process wherein two rows of dorsal epidermal cells engage in rearrangement to form a single row across the dorsal midline. Occurs at 290-340 min. |
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Term
| Ventral epidermal enclosure |
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Definition
| process by which ventral epidermal cells migrate (by epiboly) toward the ventral midline to encase underlying ells in an epithelial layer. Ensures at 310-360min (shortly after dorsal intercalation). |
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Term
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Definition
| Spreading of an epithelial sheet of cells over a substrate by changing cell shape (i.e. spreading of a sheet of cells over a group of cells). No cell divisions but leads to increased surface area. (occurs in c.elegans ventral enclosure, drosophila dorsal closure, and mammalian wound healing). |
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Term
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Definition
| Process, otherwise known as directed dilation, which results in a 3x decrease in circumference and a 4x increase in length during c. elegant development. Occurs at 360 to 600min. |
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Term
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Definition
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Term
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Definition
| Two pairs of anterior epidermal cells that migrate towards the ventral midline during c. elegans ventral epidermal enclosure. |
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Term
| which vab mutant has higher pentrance? |
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Definition
| vab-1 (60% vs. 40% for vab2) |
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Term
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Definition
| encodes an Eph receptor tyrosine kinase |
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Term
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Definition
| encodes a GPI Ephrin, which is the ligand for the VAB-1 Eph receptor tyrosine kinase (vab-2=EFN1) |
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Term
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Definition
| membrane bound ligands for Eph receptors |
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Term
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Definition
| Cell surface molecules involved in delimiting compartments in rhombomeres and axon guidance (roles in axon guidance, cell migration, hind brain patterning, angiogenesis, cancer). Interactions of ephrins and their receptors can cause repulsion of cells or attraction and adhesion. |
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Term
| How do you know that you have cloned the right gene? |
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Definition
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Term
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Definition
| A type of genetic interaction where the co-occurrence in cellular or organismal death. Synthetic lethality arises when a combination of mutations in two or more genes leads to cell death whereas a mutation in only one of these genes does not. |
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Term
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Definition
| A receptor tyrosine phosphatase which is involved in epidermal and neuronal morphogenesis during axon development |
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Term
| Sax-3 (sensory axon guidance 3) |
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Definition
| A Robo receptor, or roundabout receptor, which is involved in axon guidance and cell motility, and a regulator of actin cytoskeleton. |
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Term
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Definition
| A condition in humans where in they cannot look left or right caused by a mutation in the Robo 3 receptor, which results in defects in axon guidance. Robo 3 which is an evolutionarily conserved receptor (similar to sax-3 in c. elegans) |
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Term
| Inter-genetic non-complementation |
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Definition
| Two different loci in the heterozygous state cause a phenotype when singly there is no phenotype Good genetic evidence tfor the two genes interacting physically |
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Term
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Definition
| Mechano-sensory neurons (touch receptor neurons) in c. elegans (ex: PLML and PLMR). Vab-1 mutants have PLMs that overshoot the target site 14% of the time, whereas MYR-VAB-1 PLMs have premature axon termination 100% of the time. |
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Term
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Definition
| Myristoylation signal, sticks proteins to the inner leaflet of the membrane. Used to produce a hyperactive VAB-1 Eph TRK by constructing a constitutively active tyrosine kinase. |
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Term
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Definition
| A suppressor screen starts with a known mutation and then identifies second-site mutations that suppress the mutant phenotype. (in the example of MYR::VAB-1 this would be a mutation that restores wild type neurons). |
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Term
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Definition
| A lipid phosphatase (converts PIP3 into PIP2) and the 2nd most commonly lost tumor suppressor and a negative regulator of the insulin-signaling pathway because it antagonizes the action of P13K. (~ DAF-18 in c. elegans) |
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Term
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Definition
| A kinase which converts PIP2 into PIP3. Pi3K increases cancer risks and blocks longevity in worms |
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Term
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Definition
| In lipid and tyrosine protein phosphatase in c. elegans which is repressed by VAB-1 and represses VAB-1 (when overexpressed it promotes longevity in worms). |
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Term
| a) loss or b) gain of PTEN is a strong predictor of Herceptin resistance |
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Definition
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Term
| Which human eph receptor represses PTEN? |
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Definition
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