A detailed physical map of the porcine major histocompatibility complex (MHC) class III region: comparison with human and mouse MHC class III regions.

A detailed physical map of the porcine MHC class III region on Chr 7 was constructed with a panel of probes in a series of hybridizations on genomic pulsed field gel electrophoresis (PFGE) Southern blots. A precise organization of the 700-kb segment of DNA between G18 and BAT1 can now be proposed, with more than 30 genes mapped to it. Comparison of this region with homologous regions in human and mouse showed only minor differences.

Conservation of the RD-BF-C2 organization in the pig MHC class-III region: mapping and cloning of the pig RD gene.

The RD gene, named after the arginine (R) and aspartic acid (D) repeat in the central part of its protein, was initially mapped in the mouse H-2S subregion between C4 and BF. It was later mapped in the same position in the human MHC and here we show it is also conserved in the pig MHC class III region, close to the complement BF gene. A pig RD genomic clone was isolated from a lambda-phage library.

Polymorphic CAC/T repetitive sequences in the pig genome 1.

Three genomic clones were isolated from a size-selected pig DNA library by hybridization with a DNA-fingerprint probe. Analysis at the sequence level revealed that all three clones contain interrupted stretches of triplet repeats mainly composed of CAC and CAT triplets. Evaluation of the corresponding loci for polymorphism by Southern blot hybridization showed considerable length variation.

Pig plasma alpha-protease inhibitors PI2, PI3 and PI4 are members of the antichymotrypsin family.

Three related alpha-protease inhibitors, PI2 I, PI3 C and PI4 C2, of blood serum of the pig (Sus scrofa) were isolated. PI2 I inhibited both trypsin and chymotrypsin; PI3 C and PI4 C2 strongly inhibited chymotrypsin, but did not significantly inhibit trypsin. By using SDS-PAGE, the three proteins were found to be composed of single polypeptide chains, and molecular weights were 63,000 for PI2 I, 58,000 for PI3 C and 64,000 for PI4 C2.