WorldCat Identities

Ambros, Victor

Overview
Works: 3 works in 3 publications in 1 language and 2 library holdings
Roles: Author
Publication Timeline
Key
Publications about  Victor Ambros Publications about Victor Ambros
Publications by  Victor Ambros Publications by Victor Ambros
Most widely held works by Victor Ambros
Purification and properties of a HeLa cell enzyme able to remove the 5'- terminal protein from poliovirus RNA by Victor Ambros ( )
1 edition published in 1980 in Undetermined and held by 1 WorldCat member library worldwide
Using a rapid phenol extraction assay, an enzyme was purified from uninfected HeLa cells that can cleave the 5'-terminal protein (VPg) from poliovirus RNA. Both cytoplasmic and nuclear extracts had enzymes with similar behavior. A polypeptide of molecular weight 27,000 was the major one present in the purified preparation. Assuming that this protein is the enzyme, a very low turnover number was calculated for it. The purified enzyme would cleave the tyrosine-phosphate bond linking VPg to poliovirus RNA with minimal degradation of the RNA or of VPg. If the RNA was first treated with proteinase K to degrade VPg, leaving a small peptide on the RNA, this peptide could also be removed by the enzyme. If the RNA was degraded with T1 RNase, leaving VPg attached to a nonanucleotide, the enzyme still would cleave off VPg, although incompletely. If the RNA was degraded completely, leaving either pUp or pU attached to VPg, the enzyme would not remove the nucleotides from the protein. Thus, for the enzyme to be active requires some length of polynucleotide attached to the protein but only a short peptide need be present for the enzyme to act
Protein is linked to the 5' end of poliovirus RNA by a phosphodiester linkage to tyrosine by Victor Ambros ( )
1 edition published in 1978 in Undetermined and held by 1 WorldCat member library worldwide
Purification and partial characterization of the poliovirus RNA-linked protein (VPg) are described. VPg has been freed from the RNA by ribonuclease digestion and phenol extraction. Gel filtration chromatography of VPg-pUp (labeled with 32P) in 0.5% sodium dodecyl sulfate or 6 M guanidine HCl indicates that it has a molecular weight of about 12,000. VPg is bound to the 5' end of poliovirion RNA by a phosphodiester bond between a tyrosine residue in the VPg molecule and the 5'-terminal uridine. After acid hydrolysis of [3H]tyrosine-labeled VPg-pU, free tyrosine can be released by venom phosphodiesterase. Acid hydrolysis of VPg-p labeled with either 32P or [3H] tyrosine yields tyrosine-phosphate. There appears to be only 1 tyrosine residue per VPg molecule
MicroRNA pathways in animal development by Victor Ambros ( Visual )
1 edition published in 2009 in English and held by 0 WorldCat member libraries worldwide
(CIT): MicroRNAs are small regulatory RNA molecules, encoded in the genome, that base-pair with specific messenger RNAs and control their translation. MicroRNAs function in diverse physiological and developmental processes in animals, and in the nematode C. elegans, certain microRNAs figure prominently in the control of developmental timing by the heterochronic gene pathway. The genetic control of C. elegans developmental timing has provided a powerful model system for the genetic analysis of the function of certain microRNAs that are highly conserved between worms and mammals. C. elegans developmental timing mutants have moreover identified proteins that are part of the regulatory machinery associated with microRNAs and that could serve to mediate the regulation of microRNA activity by signaling pathways
 
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Audience level: 0.47 (from 0.00 for MicroRNA p ... to 0.47 for Purificati ...)
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English (1)