Lect 26 Molecular Regulation

Question 1

HOX Genes are responsible for:
_______ of body based on order of genes. __ genes are expressed more ______ and a smaller gene number means it is closer to the head

Gain of function mutation: _____ to _____ transformation

Loss of function mutation: _____ to _____ transformation

Answer 1

Segmentation of body.

3’ genes are expressed more anteriorly (towards the head)

GoF: anterior to posterior (head moves down)

LoF: posterior to anterior (butt moves up)

Question 2

PAX Genes are responsible for the eye disorder _____, which is the absence of the ____.

They are important for developing the ___ and the ____ organ

Answer 2

Aniridia = Absence of iris

Impt for CNS and pancreas

Question 3

Lim Proteins, if absent, can cause the embryo to lack _____

Answer 3

a head

Question 4

Dlx Genes are responsible for morphogenesis of _____, ___, and ____, this last one causes _____ when mutated

Answer 4

Appendages (arms/legs), jaw, and inner ear = Deafness when mutation

Question 5

Msx genes create the ____, which can lead to _____ mutations in babies

Answer 5

Face interactions; msx = “mask”

Can lead to cranial mutations in babies (large frontal prominence)

Question 6

FOX/Forkhead genes are responsible for the condition ____ when mutated because they develop fine ____ movements

Answer 6

What the fox say?

Causes DVD (developmental verbal dyspraxia)

develops fine orofacial movements

Question 7

Zinc Finger Proteins:
SoxA is the ___ determining region of Y chromosome
SOX9 causes _____ _____, which shows club feet and ambiguous genitalia
WT1 = ____ ___ ____, which plays a role in the kidney and gonadal development

Answer 7

SoxA = sex determining region. Think: if male doesn’t look male

SOX9 = Campomelic Dysplasia

WT1 = Wilm’s tumor supressor gene

Question 8

TGF-B Family
_____ and ____ inhibit _____, and down-regulator

If ____ is blocked effectively, the ectoderm becomes the ______ (the ___)

If ____ is not blocked, the ectoderm becomes the _____

Answer 8

Noggin and Chordin inhibit BMP4, a down-regulator

BMP4 blocked = ectoderm –> neural plate (CNS)

BMP4 not blocked = ectoderm –> epidermis

Question 9

_____ ____ found in Rogaine and Accutaine acts through the ___ gene. This means excess of _____ causes the anterior side of the body to mesh into posterior side of the body

Answer 9

Retinoic Acid (vitamin A) acts through Hox gene

Excess RA = super skeletal dwarf