Molecular Detection, Phylogenetic Analysis, and Identification of Transcription Motifs in Feline Leukemia Virus from Naturally Infected Cats in Malaysia

Abstract EN

A nested PCR assay was used to determine the viral RNA and proviral DNA status of naturally infected cats.

Selected samples that were FeLV-positive by PCR were subjected to sequencing, phylogenetic analysis, and motifs search.

Of the 39 samples that were positive for FeLV p27 antigen, 87.2% (34/39) were confirmed positive with nested PCR.

FeLV proviral DNA was detected in 38 (97.3%) of p27-antigen negative samples.

Malaysian FeLV isolates are found to be highly similar with a homology of 91% to 100%.

Phylogenetic analysis revealed that Malaysian FeLV isolates divided into two clusters, with a majority (86.2%) sharing similarity with FeLV-K01803 and fewer isolates (13.8%) with FeLV-GM1 strain.

Different enhancer motifs including NF-GMa, Krox-20/WT1I-del2, BAF1, AP-2, TBP, TFIIF-beta, TRF, and TFIID are found to occur either in single, duplicate, triplicate, or sets of 5 in different positions within the U3-LTR-gag region.

The present result confirms the occurrence of FeLV viral RNA and provirus DNA in naturally infected cats.

Malaysian FeLV isolates are highly similar, and a majority of them are closely related to a UK isolate.

This study provides the first molecular based information on FeLV in Malaysia.

Additionally, different enhancer motifs likely associated with FeLV related pathogenesis have been identified.