Week 3 Segmentation Objective 2 (genes involved in segmentation)

Question 1

Homeobox genes

Answer 1

contain highly conserved seq. of around 180 nucleotides that code for 60 amino acid domain found in homeodomain transcription factors

Question 2

Function of homeobox genes

Answer 2

play majoy function in cranial-caudal segmentation development

Question 3

Activated homeobox genes are transcribed

Answer 3

3’—>5’

Question 4

Loss of function results in

Answer 4

posterior to anterior transformations

Question 5

Gain of function results in

Answer 5

anterior to posterior transformations

Question 6

T Box genes (Tbx)

Answer 6

plays major role in development of mesoderm
family includes up to 100 genes
180-200 amino acids

Question 7

Helix-loop-helix genes

Answer 7

code for basic helix loop helix transcription factors
basic regions of proteins bind to DNA
helix-loop-helix involved in homodimerization and heterodimerization

important in myogenesis

Question 8

Forkhead (fox) genes

Answer 8

another helix-loop-helix family

expressed in many developing organs through body

Question 9

zinc finger transcription fingers

Answer 9

peptides containing a zinc region that insert into DNA double helixes

sox and WT are two examples