Abstract

The current study aimed to investigate the evolution of env-like sequences in the Egyptian cotton Gossypium barbadense. DNA sequence determination and analysis ofenv-like sequences revealed that these sequences are heterogeneous in G. barbadense. The observed sequence diversity, however, seems to preserve the coding information. Phylogenetic analysis demonstrated that plant env-like sequences group together, suggesting their monophyletic origin. Gossypium env-like sequences are, however, more closely related to elements present in other plant species.  Our result suggests thatenv-like sequences in cotton have evolved under functional constraint and likely to play a role in the life cycle of these elements.

Key words: Envelope, Gossypium, gypsy, plant retroviruses, retrotransposons, retroviruses, reverse transcriptase.  

Abbreviation

LTR: long terminal repeat, ORF: open-reading frame, PCR: polymerase chain reaction, RT: reverse transcriptase gene.