Mohammad Ayoub Mir, Ph.D.

Molecular Genetics and Microbiology
MSC08 4660
1 University of New Mexico
Albuquerque, NM 87131-0001
 
Office: CRF 307
Tel: (505) 272-4319
Fax: (505) 272-9912
E-mail: mmir@salud.unm.edu

Keywords: Cap-snatching, transcription, P-bodies, Hantavirus

Research Interests

The parasitic relationship between a virus and its host cell is well defined. Eukaryotic viruses have evolved effective means to exploit their host cells. The majority of mRNA translation within eukaryotic cells is dependent on the m7G cap, a unique structure present at the 5’ terminus of the mRNA. Although cap-dependent translation provides several advantages to the host cell, it also presents liabilities that are effectively exploited by the viruses. The minus stranded and ambisense segmented RNA viruses initiate the viral mRNA transcription through the process of “cap-snatching”. During this process viruses cleave the cellular capped mRNAs from the 5’ terminus and generate capped RNA fragments that are used as primers for the synthesis of viral mRNAs.

During routine mRNA turnover, the 5’ caps of cellular mRNAs are cleaved by decapping enzymes DCP1/DCP2, followed by 5’ to 3’ degradation by exonuclease XRN1. The components of mRNA degradation machinery including decapping enzymes DCP1/DCP2 are located in discrete cytoplasmic foci called processing bodies (P bodies) where mRNA degradation takes place. Since viruses need the 5’ caps of cellular mRNAs during transcription initiation, they have to effectively compete with cellular decapping machinery to preserve these caps from degradation.

Our research interest is focused on the viral strategies that protect the 5’ caps of cellular mRNAs from the attack of decapping machinery. Other emphasis of our research program is to identify and characterize the endonuclease required for the generation of capped RNA primer during cap snatching mechanism of viral transcription initiation. We are also analyzing the characteristics of 5’ mRNA termini that are prerequisite to qualify as a primer during cap snatching.

Selected Publications

Mir. MA, Hjelle, B. Ye, C and A. T Panganiban: Cap snatching Revised: Viral storage of cellular 5’ mRNA caps in P bodies: Proc. Natl. Acad. Sci. USA, 2008, In press

Mir. MA, and A. T Panganiban: A protein that replaces entire eIF4F complex, EMBO Journal, 2008, in press

Mir. MA, and A. T Panganiban: Role of protein-protein interaction in the translational regulation by hantavirus nucleocapsid protein, J. Virology, (2008), submitted

Mir. MA, and A. T Panganiban: Hantavirus nucleocapsid protein facilitates the ribosome loading on 5’ termini of hantaviral mRNA, J. Biol. Chem (2008), in prep.

Brown, B, Mir MA, A. T Panganiban: A trimeric N terminal region of the Sin Nombre Hantavirus Nucleocapsid protein in required for the recognition of the viral RNA panhandle, J. Virology, 2008 Revision submitted

Mir. MA and A. T Panganiban. Hantavirus Nucleocapsid protein is an RNA Chaperon. RNA, 2006, 12:272-282

Mir. MA and A. T Panganiban. Characterization of RNA chaperon activity of Hantavirus Nucleocapsid protein activity. J. Virol, 2006 Jul;80 (13):6276-85.

Mir. MA , B. Brown, B.L. Hjelle, W.A Duran and A. T Panganiban . Hantavirus N protein exhibits genus specific recognition of the v RNA panhandle, 2006, J. Virol. (13):6276-850

Mir. MA and A. T Panganiban. The hantavirus nucleocapsid protein recognizes specific features of the viral RNA panhandle and is altered in conformation upon binding. J Virol. 2005 Feb;79(3):1824-35.

Mir. MA and A. T Panganiban. Trimeric hantavirus nucleocapsid protein binds specifically with the viral RNA panhandle. J. Virol. 2004 Aug;78(15):8281-8

Mir. MA, Das, S and Dipak Dasgupta.  N - terminal tail domains of core histones in nucleosome block access of anticancer drugs, mithramycin and chromomycin, to the nucleosomal DNA. Biophysical Chemistry, 2004 ,109:121-135

Mir. MA, Majee, S., Das, S. and Dipak Dasgupta. Association of chromatin with anticancer antibiotics mithramycin and chromomycin A3. Bioor Med. Chemistry, 2003, 11(13)2791-801

Mir. MA and Dipak Dasgupta.  Association of anticancer drug mithramycin with H1 depleted chromatin: a comparison with native chromatin.   Journal of Inorganic Biochemistry, (2003),94, 72-77.

Sukanya Chaktabarty, Mir. MA and Dipak Dasgupta. Differential interaction of antitumor antibiotics chromomycin A3 and mithramycin with d(TATGCATA)2 in presence of Mg2+.  Biopolymers , (2001), 62, 131-140

Mir. MA and Dipak Dasgupta.  Association of the anticancer antibiotic chromomycin A3 with the nucleosome:  Role of core histone tail domains in binding process.  Biochemistry (2001), 40, 11578-11585

Mir. MA and Dipak Dasgupta.  Interaction of antitumor drug, mithramycin with chromatin.  Biochemical and Biophysical Research Communication. (2001), 280, 68-74

Mir. MA and Dipak Dasgupta.  Interaction of mithramycin with chromatin.  Indian Journal of Biochemistry and Biophysics, (2001), 38, 71-74