exam 2 Flashcards
(50 cards)
T/F: In Drosophila, dosage compensation is achieved by the inactivation of one of the two X-chromosomes
False
Steady state level of mRNA definition
the balance between its synthesis and degradation over time
What subunit is called linker histone
H1
What snRNP interacts with an intron sequence that is located near the branch point adenosine nucleotide
U2-snRNP
T/F: For a protein to be designated as a transcription factor, it needs to have at least one DNA-binding domain AND an activation or repression domain
True
Name the protein domain in HP1 protein that interacts with trimethylated lysine 9 in histone-3 with high affinity
Chromodomain
T/F: Regions of chromosomes near the centromeres and telomeres are generally organized into heterchromatin
True
Name the histone H2 variant (minor histone) that preferentially associates with the nucleosomes of inactive X-chromosome in female mammalian cells
macro-H2A
What is the protein that is the splicing repressor in the Drosophila sexual differentiation pathway?
Sxl
What is the protein that binds to the stretch of poly A tail on the 3’ end of mRNA?
Poly (A)-binding protein II (PABPII)
What nucleotide pair is generally present at the 3’ splice site of most of the introns in eukaryotic cells?
AG
T/F: Definitive evidence for the role of U1 snRNA in pre-mRNA splicing came from the experiments indicating that base pairing between teh 5’ splice site within the intron of the pre-mRNA and the 5’ end of U1 snRNA is required for accurate pre-mRNA splicing.
True
What is the name of the multi-protein complex that is involved in the degradation of mRNAs in the cell?
Exosome
The CTD of RNA pol 2 co-ordinates what molecular process?
RNA pol 2 mediated transcription, pre-mRNA splicing, polyadenylation of pre-mRNA
Some chromatin remodeling complex proteins have a _________ domain that helps proteins bind to acetylated histone tails
Bromodomain
T/F: The mediator complex plays a role in regulating RNA transcription by acting as a bridge between RNA polymerase II and transcription factors
True
Name the H3 tail modification that is preferentially associated with inactive X-chromosome in female mammalian cells
H3K27-trimethylation
Name the protein domain in HP1 protein with which it interacts with histone methyl transferase
Chromoshadow domain
What is the role of the nuclear lamina
It provides support to the nuclear envelope
T/F: Lamin A and C are synthesized from alternative splicing of the LMNA gene pre-mRNA and are preferentially expressed in differentiated cell types
True
How do SR proteins promote splicing?
SR proteins bind to ESE and then facilitate the recruitment of snRNPs to splice junctions
Name the non-protein coding RNA gene that is directly involved in dosage compensation in fruit flies
roX-1
The H3K27 trimethyl mark in the histone tail is generally recognized by
A subunit of polycomb repressive 1 (PRC1) complex
T/F: The nuclear lamina meshwork is tethered at the inner nuclear membrane by the farnesyl groups of lamin C and several transmembrane receptors
False
