Characterization of the ETnII-alpha endogenous retroviral element in the BALB/cJ Zhx2 ( Afr1 ) allele.
Integration of mouse endogenous retroviral (MERV) elements is responsible for an estimated 10% of spontaneous mutations that have been characterized in the laboratory mouse. We recently identified a MERV integration in the first intron of the Zinc fingers and homeoboxes 2 (Zhx2) gene in BALB/cJ mice, resulting in reduced Zhx2 expression. This integration is found in BALB/cJ but not in other BALB/c substrains, indicating that it occurred after these substrains separated in the late 1930s. We have characterized this MERV element and show here that it belongs to the ETnII-alpha class of elements. Our analysis reveals that the Zhx2 ETn element lacks a 69-bp sequence compared to most other ETn elements which may be due to recombination between two identical 13-bp elements. Three mature Zhx2 transcripts are found in the liver of BALB/cJ mice. The major transcript is spliced from Zhx2 exon 1 to the 5' ETn LTR and is polyadenylated at the 3' LTR. Of the two less abundant transcripts, one is identical to the wild-type transcript, whereas the second contains 183 bp of ETn sequence spliced between Zhx2 exons 1 and 2. We have also sequenced and analyzed products from the fas ( lpr ) ETn found in MRL/lpr mice and show that it belongs to the ETnII-beta class of elements.
Perincheri
Sudhir
S
Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, Lexington, Kentucky, 40536, USA.
Peyton
David K
DK
Glenn
Michelle
M
Peterson
Martha L
ML
Spear
Brett T
BT
D000483:Alleles; D000818:Animals; D020029:Base Pairing; D001483:Base Sequence; D020077:Endogenous Retroviruses / Q000235:genetics*; D005786:Gene Expression Regulation; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020079:Terminal Repeat Sequences / Q000235:genetics*
D012333:RNA, Messenger