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. 1995 Jun;69(6):3868–3872. doi: 10.1128/jvi.69.6.3868-3872.1995

Isolation and characterization of a low-abundance splice variant from the human cytomegalovirus major immediate-early gene region.

J A Kerry 1, A Sehgal 1, S W Barlow 1, V J Cavanaugh 1, K Fish 1, J A Nelson 1, R M Stenberg 1
PMCID: PMC189107  PMID: 7745737

Abstract

The major immediate-early (IE) gene region of human cytomegalovirus (HCMV) encodes several proteins as a result of differential RNA splicing events. By expression vector cloning of HCMV IE mRNA, we isolated and characterized a cDNA for a novel splice variant from the major IE gene region. The RNA product is a derivative of the IE55 mRNA and contains an additional splice from nucleotides 170,635 to 170,307 in the IE2 gene region (UL122), resulting in a 1.4-kb mRNA. The predicted open reading frame codes for a 164-amino-acid protein with a calculated molecular mass of 18 kDa (IE18). Mung bean nuclease analysis and PCR were used to characterize expression of IE18 mRNA in HCMV-infected cells. While the 1.4-kb mRNA was detected in infected human fibroblasts in the presence of a protein synthesis inhibitor, it was not detectable during a normal infection. However, the 1.4-kb mRNA was readily detected in infected human monocyte-derived macrophages at IE times. These results suggest that the novel IE18 mRNA exhibits cell type-specific expression indicating differential regulation of the major IE gene region in different permissive cell types.

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Selected References

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