Identification of suitable reference gene in goat peripheral blood mononuclear cells (PBMCs) infected with peste des petits ruminants virus (PPRV)

Identification of an ideal, stably expressing reference gene regardless of treatment, such as virus infection, is an important prerequisite to normalize quantitative real-time PCR (qRT-PCR). Several studies have shown variable expression of reference genes in virus-infected cells. In the present study, we evaluated the expression stability of six commonly used housekeeping genes (ACTB, GAPDH, 18S rRNA, HSP 90, POLR2A, HPRT1) as reference genes in peste des petits ruminants virus (PPRV) infected and control (uninfected) goat PBMCs at different time points - 24 h, 72 h and 120 h postinfection. Expression stability of six housekeeping genes in PPRV infected goat PBMCs was ranked using four different computational programs (NormFinder, Bestkeeper, geNorm, the comparative ΔCT method) based on their expression levels. Analysis revealed GAPDH (Glyceraldehyde-3-phosphate dehydrogenase) as the most stable reference gene in PBMCs infected with PPRV. The other housekeeping genes evaluated in the study were found to vary in their expression due to virus infection and therefore are considered unreliable as reference genes for evaluating gene expression in PBMCs infected with PPRV.