CRYSTALLIZATION AND PRELIMINARY-X-RAY ANALYSIS OF LEUKEMIA INHIBITORYFACTOR

Leukemia inhibitory factor (LIF) is a polyfunctional molecule with sig nificant and diverse biological activities. LIF is a glycoprotein secr eted by a number of different cell types in vitro. It is induced in fi broblasts, lymphocytes, monocytes and astrocytes by various inducers s uch as serum, TNF, interleukin-IP and EGF. Due to extensive and variab le glycosylation the molecular weight can range from 38 to 67 kDA. The biological functions of LIF are mediated through a receptor and a sig nal transducer, gp 1 30, which is also used by factors like interleuki n-6 (IL-6), cilliary neurotropic factor (CNTF), and oncostatin M (OSM) . Here, we report the crystallization of the non-glycosylated human-li ke LIF expressed in E. coli. The present crystals diffract to 2.0 angs trom using synchrotron radiation. They belong to the monoclinic space group C2, and the cell dimensions are a = 61.5 angstrom, b = 45.3 angs trom , c = 77.7 angstrom and beta = 112.3-degrees.