Endogenous Small Rnas In The Drosophila Soma: A Dissertation, 2010 University of Massachusetts Medical School
Endogenous Small Rnas In The Drosophila Soma: A Dissertation, Megha Ghildiyal
GSBS Dissertations and Theses
Since the discovery in 1993 of the first small silencing RNA, a dizzying number of small RNAs have been identified, including microRNAs (miRNAs), small interfering RNAs (siRNAs) and Piwi-interacting RNAs (piRNAs). These classes differ in their biogenesis, modes of target regulation and in the biological pathways they regulate.
Historically, siRNAs were believed to arise only from exogenous double-stranded RNA triggers in organisms lacking RNA-dependent RNA polymerases. However, the discovery of endogenous siRNAs in flies expanded the biological significance of siRNAs beyond viral defense. By high throughput sequencing we identified Drosophila endosiRNAs as 21 nt small RNAs, bearing a 2´-O ...
Argonautes Alg-3 And Alg-4 Are Required For Spermatogenesis-Specific 26g-Rnas And Thermotolerant Sperm In Caenorhabditis Elegans., 2010 University of Massachusetts Medical School
Argonautes Alg-3 And Alg-4 Are Required For Spermatogenesis-Specific 26g-Rnas And Thermotolerant Sperm In Caenorhabditis Elegans., Colin C. Conine, Pedro J. Batista, Weifeng Gu, Julie M. Claycomb, Daniel A. Chaves, Masaki Shirayama, Craig C. Mello
GSBS Student Publications
Gametogenesis is a thermosensitive process in numerous metazoans, ranging from worms to man. In Caenorhabditis elegans, a variety of RNA-binding proteins that associate with germ-line nuage (P granules), including the Piwi-clade argonaute PRG-1, have been implicated in maintaining fertility at elevated temperature. Here we describe the role of two AGO-class paralogs, alg-3 (T22B3.2) and alg-4 (ZK757.3), in promoting thermotolerant male fertility. A rescuing GFP::alg-3 transgene is localized to P granules beginning at the late pachytene stage of male gametogenesis. alg-3/4 double mutants lack a subgroup of small RNAs, the 26G-RNAs which target and appear to down-regulate ...
Cross-Talk Between Factors Involved In Mrna Translation And Decay: A Dissertation, 2010 University of Massachusetts Medical School Worcester
Cross-Talk Between Factors Involved In Mrna Translation And Decay: A Dissertation, Shubhendu Ghosh
GSBS Dissertations and Theses
The proper workings of an organism rely on the accurate expression of genes throughout its lifetime. An important determinant for protein production is the availability of template mRNA molecules, the net effect of which is governed by their rates of synthesis vs. their rates of degradation. Normal mRNAs are proposed to be relatively stable in the cytoplasm while present in a protective, circularized conformation – the closed loop – through eIF4G-bridged interactions with 3’-bound poly(A) binding protein (Pab1p) and 5’-bound eIF4E. Introduction of a premature nonsense codon into an otherwise normal mRNA results in its rapid destabilization in cells ...
Two Plant Viral Suppressors Of Silencing Require The Ethylene-Inducible Host Transcription Factor Rav2 To Block Rna Silencing, 2010 University of Pennsylvania
Two Plant Viral Suppressors Of Silencing Require The Ethylene-Inducible Host Transcription Factor Rav2 To Block Rna Silencing, Matthew W. Endres, Brian D. Gregory, Zhihuan Gao, Amy W. Foreman, Sizolwenkosi Mlotshwa, Xin Ge, Gail J. Pruss, Joseph R. Ecker, Lewis H. Bowman, Vicki Vance
Departmental Papers (Biology)
RNA silencing is a highly conserved pathway in the network of interconnected defense responses that are activated during viral infection. As a counter-defense, many plant viruses encode proteins that block silencing, often also interfering with endogenous small RNA pathways. However, the mechanism of action of viral suppressors is not well understood and the role of host factors in the process is just beginning to emerge. Here we report that the ethylene-inducible transcription factor RAV2 is required for suppression of RNA silencing by two unrelated plant viral proteins, potyvirus HC-Pro and carmovirus P38. Using a hairpin transgene silencing system, we find ...
Functional Interplay Between Chromatin Remodeling Complexes Rsc, Swi/Snf And Iswi In Regulation Of Yeast Heat Shock Genes, Tamara Y. Erkina, Y. Zou, S. Freeling, V. I. Vorobyev, Alexander M. Erkine
Scholarship and Professional Work – COPHS
Chromatin remodeling is an essential part of transcription initiation. We show that at heat shock gene promoters functional interactions between individual ATP-dependent chromatin remodeling complexes play critical role in both nucleosome displacement and Pol II recruitment. Using HSP12, HSP82 and SSA4 gene promoters as reporters, we demonstrated that while inactivation of SNF2, a critical ATPase of the SWI/SNF complex, primarily affects the HSP12 promoter, depletion of STH1- a SNF2 homolog from the RSC complex reduces histone displacement and abolishes the Pol II recruitment at all three promoters. From these results, we conclude that redundancy between SWI/SNF and RSC ...
5¢-O-B,G-Methylenetriphosphate Derivatives Of Nucleoside, 2010 University of Rhode Island
5¢-O-B,G-Methylenetriphosphate Derivatives Of Nucleoside, Yousef Ahmadibeni, Chandravanu Dash, S. F. J. Le Grice, Keykavous Parang
Pharmacy Faculty Articles and Research
The solid-phase synthesis of 5¢-O-b,g-methylenetriphosphates of nucleosides 1–5 is described, where a 4-acetoxy-3-arylbenzyloxy group was used as a linker.