Molecular: Zaidi Flashcards
T/F: Only tRNAs code for proteins.
False, only mRNA
What type of transcription (pro/eukaryotic) has signal factors that find the promoter region?
Prokaryotic
Eukaryotic transcription begins with binding of the _____ to the _____.
TFIID
TATA Box
What is the RNA cap made of?
7-methyl guanosine
What is the wobble hypothesis?
That the first 2 positions of the codon require accurate base-pairing, but the third can tolerate a mismatch
T/F: The genetic code is degenerate.
True
What are the 3 steps in translating a tRNA?
Initiation
Elongation
Termination
What are the stop codons?
UAA, UAG, & UGA
What do release factor proteins do?
Recognize stop codons and release completed protein from tRNA
What is the only area in the cell with gated transport?
Nucleus
What organelles use transmembrane transport in the cell?
Peroxisomes, Plastids, Mitochondria, & ER
What is the name for the sorting signals to take things into the nucleus?
NLS: Nuclear Localization Signal
What is the process of import into the nucleus?
Protein NLS recognized by importin and taken into nucleus. Ran-GEF adds GTP to complex and protein is released. Ran-GTP/importin complex leaves nucleus. Ran-GAP hydrolyzes Ran-GTP to Ran-GDP which releases importin
What is the process of export from the nucleus?
Protein with NES recognized by exportin and Ran-GTP. They exit nucleus and Ran-GAP hydrolyzes Ran-GTP to Ran-GDP releasing protein and exportin.
Which mitochondrial membrane translocators are on the outer and inner membranes?
Outer: TOM/SAM complexes
Inner: TIM22/TIM23/OXA complexes
How are proteins transported into the ER?
SRP binds to ribosome and ER signal sequence of protein and move the ribosome to a protein translocator on the ER membrane. Protein is then translated into the ER.
What do Rab and SNARE proteins do?
Rab: direct vesicle to spots on target membrane
SNARE: mediate fusion of vesicle with membrane
What is the role of M6P?
Acts as target for M6P receptor to move protein from ER into endosome
T/F: Primary cell cultures survive for a finite period of time while continuous cell lines become immortal.
True
What technology is used to overexpress and then purify/isolate a protein?
Recombinant DNA technology
What are the 3 different types of chromatography?
Ion-exchange
Gel-filtration
Affinity
What protein is used as a reporter to tag proteins?
Green fluorescent protein (GFP)
How does FRET work?
Protein X emits blue light if excited by violet light. Protein Y emits green light if excited by blue light. If X & Y are not interacting, using a violet light will cause a blue light emission. If X & Y are interacting, violet light excitation will result in a green light emission
What is the term for light-induced activation of an inert molecule to an active state?
Photoactivation
What is the term for photobleaching an area of a cell and using fluorescence recovery to monitor movement of unbleached molecules?
Fluorescence Recovery After Photobleaching (FRAP)
Where are the instructions for producing a multicellular animal contained?
In the non-coding regulatory DNA
What is the term for a cell that has been fated to develop into a specialized cell type despite changes in environment?
Determined
What is the term for a cell that can change rapidly to to changes in environment?
Completely Undetermined
What is the term for cells that can change some attributes due to environment, but not others?
Committed
What part of an axon/dendrite allows it to enlarge?
Growth cone
What control the movement of actin filaments that control movement of the growth cone?
Rho & Rac
_____ _____ are released by neighboring cells and provide contact guidance to growth cones.
Chemotactic factors
What are examples of chemotactic factors and which are attractive/repulsive?
Attractive: Netrin
Repulsive: Slit, Semaphorin
What determines whether a synapse survives?
Neurotrophic factor released by target cells
