Question

Give two examples about inducible/repressible gene expression. Explain the function of the genes, the mechanism of the regulation, and why it is important to have a way to control the level of gene expression.

Answer 1

Loiven two crampies about Inducibie , o repressible gene Expression Enampie : inducible : 1) / cactose 2)/ac repressible :) Top 2) HP Explain the function of fue genes, the mechanism of fue regulation function Gienes deide almost everything about a living being one cors more genes can affect ce-specific trait. Genes may Interact with an Individual's Enriten- ment you and change what the gene makes affect Genes Hundreds of and Internal exter- nal factor's, such as whether a person will get a particular color of Cyes (or) what diseases They may develop Some diseases, such as Sickle - Cell Anemia and Huntington's disease, are Inherited, and these are also affected by genes PI en mechanism of the regulation :- X " w W w

Eco X COM

DnaK, Dnal, GrpE Bar A SA CAMP-CPR, H-NS Class 1 Master genes fihCD FlhCD Class 2 70 fi genes fliz flit Ng genes, flid fleM The hook-basal body (HBB) formation Class 3 Late genes 28 NgKL, flic.fliD. che's, mor's Filament formation

Gene on DNA transcriptiona Primary transcript processing mRNA NUCLEUS transport CYTOSOL translation Protein

Regulation of gene expression, or gene regulation Co Includes a wide range of mechanisms that are used by cells to Increase Cor) decreased the production of specific gene products ( protein (or) R A ). Sophisticated programs of gone Expression are widery observed in biology for Grampie to trigger developmental pathway respond to Envio rontal Stimuil, or adapt to new food source. Virfually any step of gene expression can be modulected from transeriptional initiation, to RNA protesting, and to fue post - translat modifi- (allion of a protein offen, one gene regulator Controls another, and so on, a gene regulat- ory Net Work and related spe. master operon: In S. typhimurium There cies. is a regulatory Hierarchy Mat governs fue transcription of the flagellar genes of 3 - Classes the master operson (Flhos is a sole operson in class I and is transcribed by the Housekeeping Sigma factor to (070).

2.323 the sequences upstream of finde the operson ② are fairly diverse among back erice species. In E. Coli, tue f/ hol tapression is affected by several genes and physiological factors fee Heat shocks proteins ( Dwark, Dnaj, and GrpEJ, Jue piciotropic response regulator Compr) activated by acetyl Phosphate, and ta DNA - binding pootein H-Ns. more Such gen- es and factors have been discovered in other species and why it is important to have a way to control true loved of gene tapression: tue translation of mRaia Can also be controlled by a alumber of mechanisms, mostly at the lered of Initiation Recruited of the Small ribosonal Subunit can Indeed be modulated by mRNA Secondary structure, antisense RNA binding (or) protein binding. In both prokaryotes and Elkar yores, a large number of RNA bindir

pool-eins Grist, which often are directed to w Their target Sequence by the Secondary struct ure of fue transcript, which may change depending on (extain Conditions, such as tem- poratcire cord presence of a ligurd (aptamer) Some transcript aut as riborymes and Sore regulate their cupremnion.