Mapping of the Na+, K+-ATPase subunit α 2 (ATP1A2) and muscle phosphofructokinase (PFKM) genes in pig by somatic cell hybrid analysis

Two expressed sequence tags were isolated from a porcine skeletal muscle cDNA library and identified as the putative partial cDNAs of the porcine Na⁺, K⁺-ATPase subunit α 2 ( ATP1A2 ) and muscle phosphofructokinase ( PFKM ) genes after sequencing and homology search. Results of analysis of a pig–rodent somatic cell hybrid panel by PCR allowed the assignments of ATP1A2 to porcine chromosome (chr) 4 and of PFKM to porcine chr 5. These assignments support previously observed conservation of syntenic relationships between human chr 1 and porcine chr 4 and between human chr 12 and porcine chr 5.     

Expression of the interleukin-2 receptor in T lymphocytes of the rheumatoid synovial membrane

Indirect immunofluorescence was used to stain DR antigen and interleukin-2 receptor (Tac) of T-lymphocytes (Leu 4+). Tissue samples of synovial membrane were cut from arthroscopic biopsies of inflamed knees in four patients with active rheumatoid arthritis (RA). Consecutive cryostatic sections of rheumatoid sinovium were analysed using monoclonal antibodies. It was found that a high percentage of T-lymphocytes express DR antigen. In contrast the proportion of T cells expressing Tac was small. We conclude that T cell activation in synovial membrane is incomplete, and this disfunction may contribute to the chronic inflammation of RA.     

Bovine beta-lactoglobulin H: isolation by preparative isoelectric focusing in immobilized pH gradients and preliminary characterization

In spite of the fact that beta-lactoglobulin (beta-lg) was first discovered in bovine milk more than fifty years ago, and that it represents the main whey protein component in all the milks in which it has been found, its biological role and genetic evolution still remain rather uncertain. From comparative studies of the primary and tertiary structures of beta-lg and of other proteins of a similar size, the existence of a new superfamily of proteins with the function of transporter of hydrophobic molecules has been conjectured. The elucidation of the structure of beta-lg either from different species or from different genetic variants of the same species should give useful information on the evolution and function of this protein family. With this aim in mind we have now undertaken the isolation and characterization of a recently discovered, new genetic variant of bovine beta-lg. A two-step purification procedure involving preparative HPLC gel filtration and preparative IEF-IPG has been successfully carried out; it affords a good recovery of the new beta-lg in highly purified form.