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Flashcards in Genetics Deck (11)
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1
Q

Start codon

A

ATG

Methionine

2
Q

Stop codon

A

TAA
TAG
TGA

3
Q

TAA

A

Stop codon

4
Q

TAG

A

Stop codon

5
Q

TGA

A

Stop codon

6
Q

ATG

A

Methionine

7
Q

Hypoxia-induced factor

A

Transcription factor
Dimer
High O2 = unstable alpha subunit, degraded to proteasome
Low O2 = stable alpha subunit, active dimer, enters nucleus - recognises promotors (consensus sequences) of proteins which can survive in low oxygen levels

8
Q

Steroid hormones - nuclear receptors

A

Act via nuclear receptors
Nuclear receptor, no hormone bound = inactive
Steroid binds to nuclear receptor = activate nuclear receptor (dimerise)

Active nuclear receptor/hormone (transcription factor) enters nucleus
Binds to response elements to regulate the transcription of other genes

9
Q

Rubinstein-Tayra Syndrome

A

Disease due to a malfunctioning transcription factor - CRE

CRE-binding protein (CRE-BP) is phosphorylated - binds to a wide-spread response element called CRE
CRE found in many activity-depenendent genes (100s f genes)

CRE = cAMP-response element
Stimulate adenylate cyclase, increase cAMP, increase PKA
PKA phosphorylates CRE and activates

cAMP = allosteric modulator - a substance which indirectly modulates the activity of a primary ligand (modulates PKA, which P CRE to activate)

10
Q

Fibronectin

A

Splice variants

Fibroblasts - longer, attached to extracellular matrix
Hepatocytes - secreted into blood stream, involved in coagulation

11
Q

Spinal muscle atrophy

A

2 genes encode SMN genes

SMN2 gene has a silent mutation in exon - most SMN2 produced mRNA is spliced incorrectly + degraded

If there is an inactivating mutation in SMN1, only SMN2 can supply the SMN protein, but in low quantities
Enough SMN protein for embryonic life
Post-natal life leads to early pathology + mortality <10y/o