two forms of ribosomesattached ribosomes→ binds to RER(rough endoplastic reticulum) after protein translation begins; site of synthesis of secretory (exported, ☆membrane) proteins
(Nissl bodies (RER in neurons)—synthesize peptide neurotransmitters for secretion.)
free ribosomes→ unattached to any membrane; site of synthesis of cytosolic, peroxisomal, and mitochondrial proteins. biochemistrybiologyUWorld Jun 6, 2020, 6:29 AM HirotoShishido
origins of replicationParticular consensus sequence in genome where DNA replication begins.
May be single (prokaryotes) or ☆multiple (eukaryotes). geneticsbiologyUWorld Jun 3, 2020, 4:15 AM HirotoShishido
how does CpGs workThe methylation of cytosine residues in CpGs(cytosine-guanine dinucleotide repeats) prevents ☆transcription factors from binding to the promoter, effectively silencing transcription of genes not required by terminally differentiated somatic cells. pathologybiologyUWorld SIM1 May 29, 2020, 6:46 AM HirotoShishido
what initiate translation/ alternative way during apoptosisEukaryotic initiation factors☆ (eIFs) identify the 5′ cap.
caspase degrade elFs→ ☆internal ribosome entry
With this method, a distinct nucleotide sequence called the internal ribosome entry site (IRES) attracts the eukaryotic ribosome to mRNA and allows translation to begin in the middle of the mRNA sequence geneticsbiologyUWorld SIM1 May 28, 2020, 7:07 AM HirotoShishido
where is preproinsulin synthesized?/
where is it accumulated with the patients with deletion in signal sequences which can be recognized by signal recognition particles(SRPs)RER
what cell junction does calcium dependent adhesion molecules form?Adherens junction (belt desmosome, zonula adherens),
desmosome (spot desmosome, macula adherens)
→removing calcium from extracellular fluid will cause dissociation of these cadherin-mediated junctions, leading to loss of cell-cell adhesion biologypathologyUWorld SIM1 May 25, 2020, 5:49 PM HirotoShishido
sequence of telomerestelomerase(reverse transcriptase(RNA dependent DNA polymerase))adds DNA(TTAGGG) to 3' ends of chromosomes to avoid loss of genetic material with every duplication
locations of mRNA processingnucleus
・capping of 5' end
・polyadenylation 3' end
・splicing out of introns
cytoplasm
・quality control(☆interaction with Processing(P) bodies)
P bodies
①decap and degrade unwanted mRNAs
②☆store mRNA until needed for translation
③aid in translational repression by miRNAs (related to siRNAs) geneticsbiologyUWorld May 15, 2020, 12:33 AM HirotoShishido
in what locations the mutation which prevent the binding of a certain protein to lts regulatory sequence occur?(lac l→CAP site→Promotor→Operator→lac Z→lac Y→lac A)
operator locus
(a certain protein=repressor protein(product of the lac l gene))
this mutation results in increased transcription of the genes of the lac operon in lactose-deficient media, although the presence of glucose will prevent maximal transcriptional activity geneticsbiologyUWorld Apr 30, 2020, 9:56 PM HirotoShishido
polycistronic mRNAa single mRNA molecule which codes for ☆more than one protein is reffered to as a polycistronic mRNA, and while most prokaryotic mRNA molecule are polycistronic, eukaryotic mRNA is rerely polycistronic geneticsbiologyUWorld Apr 30, 2020, 5:22 AM HirotoShishido
