Crystallization and preliminary X-ray diffraction analysis of the two distinct types of zebrafish ?2-microglobulin.

ABSTRACT: ?(2)-Microglobulin (?(2)m) noncovalently associates with the heavy chain of major histocompatibility complex class I (MHC I) molecules, which bind foreign antigen peptides to control the cytotoxic T lymphocyte (CTL) immune response. In contrast to mammals, there are distinct types of ?(2)ms derived from two loci in a number of teleost species. In order to clarify the structures of the ?(2)ms, the zebrafish (Danio rerio) ?(2)ms Dare-?(2)m-I and Dare-?(2)m-II were expressed in Escherichia coli, purified and crystallized, and diffraction data were collected to 1.6 and 1.9 Å resolution, respectively. Both crystals belonged to space group P2(1)2(1)2(1). The unit-cell parameters were determined to be a = 38.2, b = 50.4, c = 50.9 Å for Dare-?(2)m-I and a = 38.9, b = 52.7, c = 65.8 Å for Dare-?(2)m-II. Each asymmetric unit was constituted of one molecule, with Matthews coefficients of 2.22 and 3.01 Å(3) Da(-1) and solvent contents of 45 and 59% for Dare-?(2)m-I and Dare-?(2)m-II, respectively. These two ?(2)m structures will provide relevant information for further studies of the structures of the MHC I complex.

SUBMITTER: Chen Z 

PROVIDER: S-EPMC4461350 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature