|1ex0, resolution 2.00Å ()|
HUMAN FACTOR XIII, MUTANT W279F ZYMOGEN
Xenopus NO38 is an abundant nucleolar chaperone and a member of the nucleoplasmin (Np) family. Here, we report high-resolution crystal structures of the N-terminal domain of NO38, as a pentamer and a decamer. As expected, NO38 shares the Np family fold. In addition, NO38- and Np-core pentamers each use highly conserved residues and numerous waters to form their respective decamers. Further studies show that NO38 and Np each bind equal amounts of the four core histones. However, NO38 prefers the (H3-H4)(2) tetramer, while Np probably prefers H2A-H2B dimers. We also show that NO38 and Np will each bind noncognate histones when the preferred partner is absent. We suggest that these chaperones must form decamers in order to bind histones and differentiate between histone tetramers and dimers. When taken together, these data imply that NO38 may function as a histone chaperone in the nucleolus.
The structure and function of Xenopus NO38-core, a histone chaperone in the nucleolus., Namboodiri VM, Akey IV, Schmidt-Zachmann MS, Head JF, Akey CW, Structure. 2004 Dec;12(12):2149-60. PMID:015576029
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
[F13A_HUMAN] Defects in F13A1 are the cause of factor XIII subunit A deficiency (FA13AD) [MIM:613225]. FA13AD is an autosomal recessive disorder characterized by a life-long bleeding tendency, impaired wound healing and spontaneous abortion in affected women.
[F13A_HUMAN] Factor XIII is activated by thrombin and calcium ion to a transglutaminase that catalyzes the formation of gamma-glutamyl-epsilon-lysine cross-links between fibrin chains, thus stabilizing the fibrin clot. Also cross-link alpha-2-plasmin inhibitor, or fibronectin, to the alpha chains of fibrin.
About this Structure
- Namboodiri VM, Akey IV, Schmidt-Zachmann MS, Head JF, Akey CW. The structure and function of Xenopus NO38-core, a histone chaperone in the nucleolus. Structure. 2004 Dec;12(12):2149-60. PMID:15576029 doi:10.1016/j.str.2004.09.017