Ten distinct circular ssDNA components, four of which encode putative replication-associated proteins, are associated with the faba bean necrotic yellows virus genome.

Abstract

Four further circular ssDNA components (C7-C10), about 1 kb in size and structurally similar to the previously described components (C1-C6) found associated with a Syrian (Sy) isolate of faba bean necrotic yellows virus (FBNYV), have been identified. Similar to C1 and C2, two of the new components (C7 and C9) encode putative replicationassociated (Rep) proteins of 33n2 and 32n7 kDa, respectively, the former of which is 90 % identical to the C10 Rep protein of milk vetch dwarf virus (MDV). C8 encodes a putative protein (17n4 kDa) whose function is unknown, but which is highly conserved between FBNYV and the other nanoviruses MDV, subterranean clover stunt virus and banana bunchy top virus. The putative protein (19n7 kDa) encoded by C10 contains an LXCXE motif, which is also

Reassortment and Concerted Evolution inBanana Bunchy Top VirusGenomes

“…DNA 5 has been shown to contain an LXCXE motif, and binding between DNA 5 products and retinoblastoma (Rb), demonstrated by yeast two-hybrid analysis, may be involved in host-cell cycle manipulation (82). In addition, more than one Rep-encoded component may be associated with virus infection in nanoviruses (22,29,30,39,63). Only one of these Rep genes, master Rep, can directly replicate non-self-replicable components, and remaining Rep-encoded components are considered to be satellite viruses (29,78,80).…”

Reconstitution of Authentic Nanovirus from Multiple Cloned DNAs

“…1), composed of iteron-like sequences flanking the IR sequences at the origin of replication with the potential of forming a stem-loop structure (8,31,50,55).…”

Banana bunchy top disease (BBTD) symptom expression in banana and strategies for transgenic resistance: A review

“…No nanovirus component has been identified that contains an ORF similar to the internal ORF encoded by BBTV DNA-R. No function has been assigned to the ORFs located on the other nanovirus-specific components (DNA-U1 and DNA-U2). Multiple satellite DNAs, encoding non-essential Reps (otherwise known as para-Reps) have also been identified associated with nanoviruses, some of which shares homology with the satellite Rep encoding components of BBTV (Katul et al, 1995;Katul et al, 1998;Sano et al, 1998). …”