The Structural Basis of Ca~(2+) Transport by The Ca~(2+-)ATPase From Skeletal Sarcoplasmic Reticulum / 生物化学与生物物理进展

The Ca2+-ATPase of sarcoplasmic reticulum is a Ca2+ pump that plays a key role in regulating cytosol calcium concentration in muscle cells. It undergoes a sequential conformational transition during the transport process. According to the classical E1/E2 theory, in the E1 state the binding sites have high affinity and open to the cytoplasm, whereas in the E2 state the binding sites have low affinity and face the luminal side. Crystal structures of several states during the reaction cycle of Ca2+-ATPase have been solved recently, including a Ca2+-bound form (E1-2Ca2+), a Ca2+-unbound form stabilized by a potent inhibitor thapsigargin (TG) (E2-TG), an ATP-bound form (E1-ATP), an E1-P-ADP state, and an E2-Pi state. The details of these crystal structures and the relationship between structure and function of Ca2+-ATPase during reaction cycle were summarized, and the issues to be addressed in future research were raised.

CLONING AND SEQUENCE ANALYSIS OF THE LIGHT CHAIN VARIABLE REGION GENE OF MONOCLONAL ANTI-IDIOTYPIC ANTIBODY NP30 OF SCHISTOSOMA JAPONICUM / 中国寄生虫学与寄生虫病杂志

Objective] To amplify and sequence the light chain of anti idiotypic monoclonal antibody NP30 of Schistosoma japonicum. [Methods] By comparing the conserved regions at each end of the nucleotide sequences of murine germ line genes enco ding FR1 and FR4 regions of immunoglobulin light chain variable regions, we designed a set of primers for amplification of V L gene. The hybridoma cells secreting anti idiotypic monoclonal antibody NP30 of Schistosoma japonicum were cultured and their genome DNAs were extracted and used as templates for PCR. The PCR product was then cloned into pUC19 vector. The recombinants were sequenced by Sanger′s method. The V L gene was compared with GenBank and published mouse V L genes. [Results] The full length of V L gene was 318 bp. The V L gene was a member of mouse Ig ? light chain subgroup IV and generated from rearrangement of germ line V and J? 4 genes. The V L gene sequence has been registered by GenBank(accession No. AF206720). [Conclusion] The obtained V L gene was a potentially functional gene of anti idiotypic monoclonal antibody NP30 of Schistosoma japonicum .