First Author | Mitsuda T | Year | 1992 |
Journal | J Autoimmun | Volume | 5 |
Issue | 3 | Pages | 277-87 |
PubMed ID | 1388635 | Mgi Jnum | J:1159 |
Mgi Id | MGI:49691 | Doi | 10.1016/0896-8411(92)90143-e |
Citation | Mitsuda T, et al. (1992) The murine Sm-D autoantigen: multiple genes, genetic polymorphism, evolutionary conservation and lack of intervening sequences in the coding region. J Autoimmun 5(3):277-87 |
abstractText | Antibodies to the Sm nuclear antigen are diagnostic of systemic lupus erythematosus (SLE). MRL/Mp-lpr/lpr mice develop a similar illness, and a proportion also develop anti-Sm. To understand better anti-Sm reactivity in this murine model, we have cloned the murine Sm-D autoantigen. One cDNA clone was 517 bp long with an open reading frame of 357 nucleotides, encoding a 13.3 kDa protein of 119 amino acids. At the nucleotide level, the murine Sm-D cDNA was 89.8% homologous with human Sm-D (94% in the coding region), yet there was identity at the protein level, including a Gly-Arg nine-fold repeated C-terminus motif. Southern blot analysis of PstI-digested genomic DNA from seven mouse strains demonstrated a 7.8 kb band in every strain; in addition, a 2.8 kb band was seen in AKR/J, LG/J and MRL/Mp-lpr/lpr. PCR amplification of genomic DNA showed a single Sm-D gene product of 360 bp, which indicated a lack of intervening sequences. The Sm-D protein is thus highly conserved in evolution, probably owing to its essential role in the physiology of the cell. |