Macromolecules II May 4, 2009 Jane Yu Transfer-messenger

Скачать презентацию Macromolecules II May 4, 2009 Jane Yu Transfer-messenger Скачать презентацию Macromolecules II May 4, 2009 Jane Yu Transfer-messenger

29852-j_yu_tmrna.ppt

  • Количество слайдов: 12

>Macromolecules II May 4, 2009 Jane Yu  Transfer-messenger RNA Macromolecules II May 4, 2009 Jane Yu Transfer-messenger RNA

>Discovery of tmRNA a small, stable RNA Ray and Apirion, 1979 Jain, et al. Discovery of tmRNA a small, stable RNA Ray and Apirion, 1979 Jain, et al. 1982

>Where is tmRNA found? All sequenced eubacteria Some rare mitochondrial and plastidial genomes in Where is tmRNA found? All sequenced eubacteria Some rare mitochondrial and plastidial genomes in simple eukaryotes such as diatoms. Some phage genomes No nuclear genomes

>What is tmRNA? mRNA-like and tRNA-like properties What is tmRNA? mRNA-like and tRNA-like properties

>Structure of tmRNA Structure of tmRNA

>Ribosomal RNA is normally recycled post-translation Ribosomal RNA is normally recycled post-translation

>tmRNA “rescues” ribosomes stalled during translation of mRNA lacking stop codons.   tmRNA “rescues” ribosomes stalled during translation of mRNA lacking stop codons. A ribosome stuck with nonstop RNA

>tmRNA “rescues” ribosomes stalled during translation of mRNA lacking stop codons.   tmRNA “rescues” ribosomes stalled during translation of mRNA lacking stop codons. A sad ribosome stuck with nonstop RNA

>tmRNA also:  1) mediates degradation of the aberrant mRNA   2) adds tmRNA also: 1) mediates degradation of the aberrant mRNA 2) adds a degradation tag to the aberrant protein for directed proteolysis Functions of tmRNA

>The tmRNA/SmpB complex The tmRNA/SmpB complex

>Trans-translation Trans-translation

>Role in human disease Vital for normal growth in: Mycobacterium pneumoniae Neisseria gonorrhaeae Vital Role in human disease Vital for normal growth in: Mycobacterium pneumoniae Neisseria gonorrhaeae Vital for pathogenesis in: Salmonella typhimurium (MP survival) Yersinia pseudotuberculosis (T3SS)