Impaired myocardial Ca 2+ cycling is a critical contributor to the development of heart failure (HF), causing changes in contractile function and structure remodeling heart. Within cardiomyocytes, regulation sarcoplasmic reticulum (SR) storage release largely dependent on handling proteins, such as SR ATPase (SERCA2a) pump. During relaxation phase cardiac cycle (diastole), SERCA2a plays role tr...

PURPOSE Pinin (Pnn/DRS/memA) is a cell-adhesion-related and nuclear protein that has been identified as central in the establishment and maintenance of corneal epithelial cell-cell adhesion. To begin the elucidation of the role of Pnn within the nucleus of corneal epithelial cells, this study was undertaken to identify the proteins that bind to Pnn. METHODS Yeast two-hybrid analyses were perf...

Arginine-Serine (RS) domain-containing proteins are RNA binding proteins with multiple functions in RNA metabolism. In mammalian cells this group of proteins is also implicated in regulation and coordination of cell cycle and apoptosis. In trypanosomes, an early branching group within the eukaryotic lineage, this group of proteins is represented by 3 members, two of them are SR proteins and hav...

Sr(2+) triggers neurotransmitter release similar to Ca(2+), but less efficiently. We now show that in synaptotagmin 1 knockout mice, the fast component of both Ca(2+)- and Sr(2+)-induced release is selectively impaired, suggesting that both cations partly act by binding to synaptotagmin 1. Both the C(2)A and the C(2)B domain of synaptotagmin 1 bind Ca(2+) in phospholipid complexes, but only the...

PDZK1 is a scaffold protein containing four PDZ protein interaction domains, which bind to the carboxy termini of a number of membrane transporter proteins, including ion channels (e.g., CFTR) and cell surface receptors. One of these, the HDL receptor, scavenger receptor class B type I (SR-BI), exhibits a striking, tissue-specific dependence on PDZK1 for its expression and activity. In PDZK1 kn...

The p54 protein was previously identified by its reactivity with an autoantiserum. We report here that p54 is a new member of the SR family of splicing factors, as judged from its structural, antigenic, and functional characteristics. Consistent with its identification as an SR protein, p54 can function as a constitutive splicing factor in complementing splicing-deficient HeLa cell S100 extract...