Txhua chav tsev ribosomal muaj RNA nucleotide molecules thiab lawv cov proteins cuam tshuam. Thaum ob lub subunits no koom ua ke, nws tsim cov ribosomes nquag ntawm kev sib txuas ntawm cov protein. Qhov kev koom ua ke ntawm ob lub subunits no tsuas yog ua los ntawm magnesium ions tam sim no hauv cell.
Yuav ua li cas ribosomal subunits tuav ua ke?
Ob lub subunits (30S thiab 50S) ntawm cov kab mob 70S ribosome yog tuav ua ke los ntawm 12 dynamic txuas nrog RNA–RNA, RNA–protein, thiab protein-protein kev sib cuam tshuam. Cov txheej txheem ntawm kev tsim choj, xws li seb tag nrho cov txuas hniav no tau tsim ib txhij los yog nyob rau hauv ib qho kev txiav txim, tsis to taub.
Yuav ua li cas ions ua lub luag haujlwm tseem ceeb hauv kev ua kom ob lub subunits ntawm ribosome ua ke?
Mg2+ yog qhov tseem ceeb rau ob txoj haujlwm tseem ceeb xws li kev ruaj khov ntawm cov qauv thib ob ntawm rRNA thiab khi ntawm ribosomal proteins rau rRNA. Yog li, cov ion yuav tsum tau khaws ob chav ribosomal ua ke thaum lub sij hawm tsim cov protein yog Mg +.
Nws yog qhov tseem ceeb rau kev khi ntawm ribosomal subunits?
rRNA plays lub luag haujlwm tseem ceeb hauv kev ua haujlwm ntawm peptidyl transferase, lub chaw catalytic ntawm ribosome lub luag haujlwm rau peptide daim ntawv cog lus. … Hauv tsab ntawv ceeb toom no, peb txhais cov txheej txheem me me ntawm rRNA nucleotides uas feem ntau yuav ncaj qha koom nrog kev khi ntawm tRNA hauv cov chaw ua haujlwm.ntawm lub loj ribosomal subunit.
Dab tsi yog ob lub ribosomal subunits?
Txhua ribosome yog ib qho nyuaj ntawm cov proteins thiab tshwj xeeb RNA hu ua ribosomal RNA (rRNA). Hauv ob qho tib si prokayotes thiab eukaryotes nquag ribosomes yog tsim los ntawm ob lub subunits hu ua qhov loj thiab me subunit. … Lub subunit loj yog complex thiab muaj ob protuberances, ib lub hav thiab ib tug stalk raws li zoo raws li ib tug polypeptide tawm qhov chaw.
