Bio studies chap 14

Ricin

Ribosome inactivating protein

Gene expression

The process by which the DNA the synthesis of protein

Protein between what

Genotype and phenotype

Beadle and Tatum (1941)

Studied neurospora crassa by generating nutritional mutants

Beadle and Tatum’s conclusion

Established one gene to protein/polypeptide hypothesis + gene to enzyme hypothesis

Arginine that neurospore mutant require

Ornithine and citruline

What makes RNA different from DNA

1. Single stranded (usually)

2. Ribose not deoxyribose

3. Uracil to replace thymine

Transcription (in nucleus of eukaryotes)

From DNA to RNA sequence

Translation (cytoplasm of eukaryotes and prokaryotes)

From RNA to amino acids sequence

2 letters can

Give 8 codes

3 letters can

64 codes

Stop codon

UAA, UGA, UAG

Start codon

AUG: methionine

What is nearly universal?

Genetic code

Transcription: initiation

RNA polymerase to promoter that targets and identify sequence

Transcription: elongation

RNA polymerase adding nucleoside triphosphate from 3 and 5 end

Transcription: termination

RNA polymerase stops at terminator sequence (UAA, UGA, UAG) and detached

Splicesome

RNA processing agent

Transfer RNA

Transport/transfer specific amino acid

Anticodon

Antiparallel and complementary to mRNA codon

Aminoacyl-tRNA synthetase

That provides space and catalyzes charging tRNA

Methionine

AUG

Lysine

AAG

Phenylalanine

UUU

Glysine

GGC

Translation: imitation

Small ribosome subunit to recognition sequence on mRNA 5 end, anticodon, and large subunit

Translation: elongation

New tRNA in A-site, releasing P-site amino acids, polypeptide bonds form between released amino acid and new one from A-site

Translation: termination

Using “release factor” to release tRNA and polypeptide while subunits separate

Polyribosome

mRNA/ribosome assembly

What can ribosomes simultaneously do

Translating mRNA

Signal sequence

Address label that determine its determine

Proteolysis

Cleaving/breaking polypeptide to fold into different shapes

Glycosylation

Adding glucose for targeting and recognizing

Phosphorylation

Adding phosphate group to alter protein’s shape