| Structural highlights
Function
POL2_CPMVS Movement protein: transports viral genome to neighboring plant cells directly through plasmosdesmata, without any budding. The movement protein allows efficient cell to cell propagation, by bypassing the host cell wall barrier. Acts by forming a tubular structure at the host plasmodesmata, enlarging it enough to allow free passage of virion capsids. Binds to GTP and to single-stranded RNA and single-stranded DNA in a non-sequence-specific manner.[1] [2] [3] [4] The cleavable C-terminus of small coat protein seems to be involved in the packaging of the virion RNAs. Also seems to act as suppressor of post-transcriptional gene silencing (PTGS), a mechanism of plant viral defense that limits the accumulation of viral RNAs.[5] [6] [7] [8]
Publication Abstract from PubMed
Empty virus-like particles (eVLPs) of Cowpea mosaic virus (CPMV) are currently being utilized as reagents in various biomedical and nanotechnology applications. Here, we report the crystal structure of CPMV eVLPs determined using X-ray crystallography at 2.3 A resolution and compare it with previously reported cryo-electron microscopy (cryo-EM) of eVLPs and virion crystal structures. Although the X-ray and cryo-EM structures of eVLPs are mostly similar, there exist significant differences at the C terminus of the small (S) subunit. The intact C terminus of the S subunit plays a critical role in enabling the efficient assembly of CPMV virions and eVLPs, but undergoes proteolysis after particle formation. In addition, we report the results of mass spectrometry-based proteomics analysis of coat protein subunits from CPMV eVLPs and virions that identify the C termini of S subunits undergo proteolytic cleavages at multiple sites instead of a single cleavage site as previously observed.
Crystal Structure and Proteomics Analysis of Empty Virus-like Particles of Cowpea Mosaic Virus.,Huynh NT, Hesketh EL, Saxena P, Meshcheriakova Y, Ku YC, Hoang LT, Johnson JE, Ranson NA, Lomonossoff GP, Reddy VS Structure. 2016 Apr 5;24(4):567-75. doi: 10.1016/j.str.2016.02.011. Epub 2016 Mar, 24. PMID:27021160[9]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Taylor KM, Spall VE, Butler PJ, Lomonossoff GP. The cleavable carboxyl-terminus of the small coat protein of cowpea mosaic virus is involved in RNA encapsidation. Virology. 1999 Mar 1;255(1):129-37. PMID:10049828
- ↑ Canizares MC, Taylor KM, Lomonossoff GP. Surface-exposed C-terminal amino acids of the small coat protein of Cowpea mosaic virus are required for suppression of silencing. J Gen Virol. 2004 Nov;85(Pt 11):3431-5. PMID:15483261 doi:http://dx.doi.org/85/11/3431
- ↑ Liu L, Grainger J, Canizares MC, Angell SM, Lomonossoff GP. Cowpea mosaic virus RNA-1 acts as an amplicon whose effects can be counteracted by a RNA-2-encoded suppressor of silencing. Virology. 2004 May 20;323(1):37-48. PMID:15165817 doi:http://dx.doi.org/10.1016/j.virol.2004.02.013
- ↑ Carvalho CM, Pouwels J, van Lent JW, Bisseling T, Goldbach RW, Wellink J. The movement protein of cowpea mosaic virus binds GTP and single-stranded nucleic acid in vitro. J Virol. 2004 Feb;78(3):1591-4. PMID:14722313
- ↑ Taylor KM, Spall VE, Butler PJ, Lomonossoff GP. The cleavable carboxyl-terminus of the small coat protein of cowpea mosaic virus is involved in RNA encapsidation. Virology. 1999 Mar 1;255(1):129-37. PMID:10049828
- ↑ Canizares MC, Taylor KM, Lomonossoff GP. Surface-exposed C-terminal amino acids of the small coat protein of Cowpea mosaic virus are required for suppression of silencing. J Gen Virol. 2004 Nov;85(Pt 11):3431-5. PMID:15483261 doi:http://dx.doi.org/85/11/3431
- ↑ Liu L, Grainger J, Canizares MC, Angell SM, Lomonossoff GP. Cowpea mosaic virus RNA-1 acts as an amplicon whose effects can be counteracted by a RNA-2-encoded suppressor of silencing. Virology. 2004 May 20;323(1):37-48. PMID:15165817 doi:http://dx.doi.org/10.1016/j.virol.2004.02.013
- ↑ Carvalho CM, Pouwels J, van Lent JW, Bisseling T, Goldbach RW, Wellink J. The movement protein of cowpea mosaic virus binds GTP and single-stranded nucleic acid in vitro. J Virol. 2004 Feb;78(3):1591-4. PMID:14722313
- ↑ Huynh NT, Hesketh EL, Saxena P, Meshcheriakova Y, Ku YC, Hoang LT, Johnson JE, Ranson NA, Lomonossoff GP, Reddy VS. Crystal Structure and Proteomics Analysis of Empty Virus-like Particles of Cowpea Mosaic Virus. Structure. 2016 Apr 5;24(4):567-75. doi: 10.1016/j.str.2016.02.011. Epub 2016 Mar, 24. PMID:27021160 doi:http://dx.doi.org/10.1016/j.str.2016.02.011
|
