Chinese Hamster Ovary retrovirus (RCHO) is a C-type retrovirus that in integrating recognizes a target G-repeat sequence belonging to the short interspersed element family of retroposons. This retrovirus has been detected in CHO-K1 cells and in Chinese hamster liver (Lie et al. 1994). The genomic structure of RCHO-K1 is 9.6 Kb size including LTRs 465 and 456 nt. The internal region of this retrovirus displays a Primer Binding Site (PBS) complementary to a tRNAPro, two Open Reading Frames (ORFs) gag-pro and pol (pol displays three frameshiftings), an ORF for env gene, and also a Polypurine Tract (PPT) adjacent to the 3´LTR (Lie et al. 1994).
Figure not to scale. If present, long terminal repeats (LTRs) have been highlighted in blue. Amino acid motifs noted with lines indicate the conserved residues in each protein domain, abbreviations below mean:
||DU or DUT=dUTPase
||TAV or IBMP=transactivator/viroplasmin or inclusion body matrix protein
||PBS=primer binding site
||ATF=aphid transmission factor
||VAP=virion associated protein