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Flashcards in More molecular biochem Deck (16):
1

Xeroderma pigmentosum defect

nucleotide excision repair. pts cn't repari pyrimadine dimers that form d/t UV light exposure

2

Hereditary nonpolyposis colorectal cancer defect

mismatch repair defect.

3

ataxia telangiactasia defect

ATM gene defect. mutation results in poor non-homologous end joing after double stranded breaks

4

mRNA processing in the nucleus

capping of 5' end, polyadenylation of 3' end, splicing of introns

5

alpha amanitin

found in death cap mushrooms. inhibits RNA pol II (makes mRNA). causes severe haptotoxicity if ingested.
recall that RNA pol I makes rRna, and RNA pol III makes tRNA

6

mRNA quality control

occurs at cytoplasmic P bodies.
they contain exonucleases, decapping enzymes, and microRNAS.

7

Significance of autoantibodies to splicesomal snRNPs (small nuclear ribonuclear proteins) and autoantibodies to U1RNPs

Anti-smith antibodies are highly specific for lupus (splicesomal snRNPs), antibodies against U1RNPs are specific for mixed connective tissue disease

8

tRNA structure

looks like a T. amino acid is charged on the ACC end (3'). T arm carries the tymine, T-pseudouridine, cytosine sequence for binding to tRNA-ribosome. D arm carries the sequence for recognition by the aminoacyl-tRNA synthetase (dihydrouracil residues)

9

Important energy molecules used in protein synthesis

ATP required for charging a tRNA (activation)
GTP required for initiation of protein synthesis (initiation factors assemble the 40S subunit with the initiator tRNA. they are released when the mRNA and the ribosomal 60S subunit assemble with the complex). GTP is also used for translocation

10

Rough ER: function, specialized types

make proteins for secretion. Also does N-linked oligosaccharide addition. in neurons, the RER is called a Nissl body. Nissl bodies synthesize neurotransmitters.

11

Smooth ER function

makes steroid synthesis and detoxification of drugs and poisons.

12

Function of Golgi

modified N-oligosaccharides on asparagine. Adds O oligosacchraides on serine and threonine. Adds mannose-6-P for trafficking of proteins to lysosomes

13

I cell disease

defect in addition of mannose-6-P for trafficking of proteins to lysosomes. causes excretion of lysosomal proteins. symptoms: coarse facial features, clouded corneas, restricted joint movement.

14

COPI vs COPII

trafficking proteins. COPI is retrograde. within the Golgi and golgi to ER.
COPII: anterograde. Golgi-Goli anterograde; ER to Golgi

15

What is digested in the peroxisome?

very-long-chain fatty acids, branched chain fatty acids, amino acids

16

What disease is associated with defective proteosomes?

Parkinsons