单细胞mRNA测序 - 陈巍学基因(11)
单细胞mRNA测序是很有用的科研方法。
本课程介绍其中2种:Clontech公司的SMART-seq方法,和EpiCentre公司的TargetAmp方法。2种方法各有巧妙,即大量扩增了核酸,又尽可能减少核酸扩增过程中的偏差、失真。
细胞质处理小体(P-小体)和mRNA的周期
Roy Parker (U. Colorado Boulder/HHMI) Part 2: P-bodies and the mRNA Cycle
In the second part of this lecture, I will provide an overview of why the regulation of translation and mRNA degradation is an important aspect of the control of gene expression in eukaryotic cells. In addition to the translating pool of mRNAs associated with polysomes, recent experiments have identified P-bodies and stress granules as specific cytoplasmic compartments wherein untranslated mRNAs accumulate. In addition to mRNAs, P-bodies tend to contain translation repressors and mRNA degradative enzymes, while stress granules reflect mRNAs in association with some translation initiation factors and RNA binding proteins. P-bodies and stress granules interact and suggest a dynamic process wherein eukaryotic mRNAs remodel their interacting proteins and enter and exit translation, thereby affecting the control of mRNAs in the cytoplasm. We are interested in defining the mechanisms by which P-bodies and stress granules assemble and how cells regulate the movement of mRNAs between these different biochemical and cell biological compartments. Several approaches will be described including biochemical and genetic analyses of known proteins modulating these events, as well as the identification of new factors affecting P-body and stress granule formation and function.
In 2012, Roy Parker joined the University of Colorado, Boulder after many years at the University of Arizona.
Protein synthesis: mRNA surveillance by the ribosome
Rachel Green (Johns Hopkins U., HHMI) 2: Protein synthesis: mRNA surveillance by the ribosome
Talk Overview:
In her first talk, Green provides a detailed look at protein synthesis, or translation. Translation is the process by which nucleotides, the “language” of DNA and RNA, are translated into amino acids, the “language” of proteins. Green begins by describing the components needed for translation; mRNA, tRNA, ribosomes, and the initiation, elongation, and termination factors. She then explains the roles of these players in ensuring accuracy during the initiation, elongation, termination and recycling steps of the translation process. By comparing translation in bacteria and eukaryotes, Green explains that it is possible to determine which components and steps are highly conserved and predate the divergence of different kingdoms on the tree of life, and which are more recent adaptations.
Green’s second talk focuses on work from her lab investigating how ribosomes detect defective mRNAs and trigger events leading to the degradation of the bad RNA and the incompletely translated protein product and to the recycling of the ribosome components. Working in yeast and using a number of biochemical and genetic techniques, Green’s lab showed that the protein Dom34 is critical for facilitating ribosome release from the short mRNAs that result from mRNA cleavage. Experiments showed that Dom34-mediated rescue of ribosomes from short mRNAs is an essential process for cell survival in higher eukaryotes.
Speaker Biography:
Rachel Green received her BS in chemistry from the University of Michigan. She then moved to Harvard to pursue her PhD in the lab of Jack Szostak where she worked on designing catalytic RNA molecules and investigating their implications for the evolution of life. As a post-doctoral fellow at the University of California, Santa Cruz, Green began to study how the ribosome translates mRNA to protein with such accuracy.
Currently, Green is a Professor of Molecular Biology and Genetics at the Johns Hopkins School of Medicine and an Investigator of the Howard Hughes Medical Institute. Research in her lab continues to focus on the ribosome and factors involved in the fidelity of eukaryotic and prokaryotic translation.
Green is the recipient of a Johns Hopkins University School of Medicine Graduate Teaching Award as well as the recipient for numerous awards for her research. She was elected to the National Academy of Sciences in 2012.