The primary structure of red clover mottle virus middle component RNA

Cowpea mosaic virus M RNA is translated in vitro as well as in vivo into two C-coterminal polyproteins of Mr 105K and 95K. Initiation of translation of the 95K protein gene occurs at an AUG codon at position 512 of M RNA, 351 nucleotides downstream of the initiation codon of the 105K protein gene at position 161. By employing an in vitro transcription and translation system it was determined that this 351 nucleotide sequence has the capacity to direct ribosomes to initiate translation at a downstream start codon. This effect is independent of the position of this sequence in an mRNA. Furthermore, evidence has been obtained that scanning ribosomes can bypass the AUG at position 161. Thus, both leaky scanning and internal entry are mechanisms for the initiation of translation of the 95K protein gene.

Section: Discussionmentioning

confidence: 99%

The sequence between nucleotides 161 and 512 of cowpea mosaic virus M RNA is able to support internal initiation of translation in vitro

Verver

Gall

Kammen

et al. 1991

“…Within the first of these regions is a stretch of 10 nt, 5' UUUUGUGUGU Y, found in GFLV that is also found in the 3' UTR of the nepovirus ArMV (Bertioli et al, 1991), the comovirus RCMV (Shanks et al, 1986) and in the 3' UTR of SLRV RNA-2. However, this sequence is not found in the 3' UTR of other nepoviruses and comoviruses.…”

Section: Tnca(c/t)ga(a/g)ga(c/t)(c/t)tngtnccmentioning

confidence: 99%

“…Although most of the nepoviruses and comoviruses have 3' UTRs shorter than that of SLRV RNA-2 [nepoviruses, TBRV, 301 nt (Meyer et al, 1986), GCMV, 251 nt (Brault et al, 1989), GFLV, 212 nt (Serghini et al, 1990) and RRV, 397 nt (Blok et al, 1992); comoviruses, RCMV, 263 nt (Shanks et al, 1986), CPSMV, 471 nt (Chen& Bruening, 1992), CPMV, 179 nt (van Wezenbeek et al, 1983), BPMV, 455 nt (MacFarlane et al, 1991)], TomRSV (Rott et al, 1991) has a significantly longer 3' UTR (1550 nt).…”

Section: Tnca(c/t)ga(a/g)ga(c/t)(c/t)tngtnccmentioning

confidence: 99%

Nucleotide sequence of the coat protein genes of strawberry latent ringspot virus: lack of homology to the nepoviruses and comoviruses

Everett

Milne

Forster

1994

The sequence of the 3'-terminal 2424 nucleotides of RNA-2 of the flowering cherry strain of strawberry latent ringspot virus (SLRV) was determined from eDNA clones. The sequence contains a reading frame in the virus-sense strand of 2070 nucleotides, a 3' untranslated region of 552 nucleotides and a T-terminal poly(A) tract. The positions of the two coat proteins of SLRV within the reading frame were determined from sequence data obtained by N-terminal sequencing using Edman degradation. The larger coat protein with an M r of 43K is located 5' of the smaller coat protein of 27K, and the two proteins are apparently cleaved at a Ser-Gly bond. Although there are numerous similarities between SLRV and the nepoviruses and comoviruses, there is no significant homology between the SLRV coat proteins and the coat proteins of either group. Furthermore, the hydropathy profiles of the SLRV coat proteins are unlike those of either group. No comparisons could be made with the fabaviruses owing to lack of sequencing information. This lack of homology suggests that SLRV is more distantly related to the nepoviruses and comoviruses than has been considered previously.

“…Sequence data have been published for RNA-2 on single isolates of APMV (Shindo et al, 1993), BPMV (MacFarlane et al, 1991), CPMV (van Wezenbeek et al, 1983), CPSMV (Chen & Bruening, 1992) and RCMV (Shanks et al, 1986). Using the published nucleotide sequence data, Shindo et al (1993) aligned the deduced amino acid sequences for the MP, LCP and SCP for APMV, BPMV, CPMV, CPSMV and RCMV to show that the distantly related APMV had a genome structure consistent with that of other comoviruses.…”

Section: Sequence Comparisons Among Comovirus Rna-2mentioning

confidence: 99%

Diversity among isolates of squash mosaic virus.

Haudenshield

Palukaitis

1998

cDNA clones of RNA-2 of two isolates of squash mosaic virus (SqMV) were constructed and sequenced, revealing 87 % sequence similarity. In Northern blot hybridization analyses, DNA probes made from these clones defined two SqMV hybridization subgroups. This grouping was verified by reciprocal hybridizations of purified RNA from five SqMV isolates, as probed with cDNA made from a member of each subgroup. Comparison of the RNA-2 sequence among the two SqMV isolates, and the reported sequence of other comoviruses, showed