Characterization of human cytomegalovirus UL146 transcripts

BackgroundThe genome of human cytomegalovirus (HCMV) has been studied extensively, particularly in the UL/b′ region. In this study, transcripts of one of the UL/b′ genes, UL146, were identified in 3 HCMV isolates obtained from urine samples of congenitally infected infants.MethodsNorthern blot hybridization, cDNA library screening, and RACE-PCR were used.ResultsAll sequences of clones from a cDNA library were about 3225 bp in length with the same 5′ and 3′ ends. The results were accordant with that analyzed by Northen-blot and RACE-PCR in three HCMV clinical isolates. The transcript initiated from the region upstream of UL146 flanking region and terminated just downstream of UL132 including UL146, UL147, UL147A, UL148, and UL132 ORFs. Treatment of the infected cells with phosphonoacetic acid inhibited its transcription.ConclusionsUL146 ORF was transcribed with 4 downstream ORFs from UL147 to UL132 at true late kinetics. The transcript of UL146 initiated at 73 nt upstream of UL146 and terminated just downstream of UL132 in the 3 clinical isolates.

► Transcripts of UL146 were identified in 3 HCMV isolates obtained from congenitally infected infants. ► Northern blot hybridization, cDNA library screening, and RACE-PCR were used. ► UL146 ORF was transcribed with 4 downstream ORFs from UL147 to UL132 at true late kinetics. ► The transcript of UL146 initiated at 73 nt upstream of UL146 and terminated just downstream of UL132.