MOLECULAR CHARACTERISATION OF TOMATO YELLOW LEAF CURL VIRUS Alm [Ma:Bk:02] IN MOROCCO: COMPLETE SEQUENCE AND GENOME ORGANISATION
N. Boukhatem, S. Jdaini, Y. Muhovsky, J.M. Jacquemin, C.L. Del Rincóne, M.J. Diéz, A. Bouali
Tomato yellow leaf curl disease is the main limiting factor for tomato (Solanum lycopersicum) production in Morocco. The PCR product obtained from a symptomatic sample was cloned and the complete DNA sequence (2781 bp) of the monopartite genome is reported of a Tomato yellow leaf curl virus isolate from north-east Morocco identified as TYLCV-Alm [Ma:Bk:02]. The circular genomic DNA contains six open reading frames encoding proteins of molecular weights ranging from 11 kDa to 40 kDa. Two proteins (V1 and V2) are located on the virion-sense strand whereas four other proteins (C1, C2, C3 and C4) are located on the complementary-sense strand. The two open reading frame groups are separated by an intergenic region of about 300 nucleotides, comprising a sequence capable of forming a stable hairpin loop structure containing the motif 5'-TAATATTAC-3'. The complete sequence obtained was closely related to that of Tomato yellow leaf curl virus (TYLCV) with nucleotide sequence identity ranging from 93% to 99%. Sequence comparison with other geminiviruses showed that the TYLCV isolate from north-eastern Morocco belongs to genus Begomovirus from the Old World, and is at least 99% identical to the sequence of Almeria TYLCV [TYLCV-( Alm)].