Two novel mutations of Wiskott-Aldrich syndrome: the molecular prediction of interaction between the mutated WASP L101P with WASP-interacting protein by molecular modeling.
Wiskott-Aldrich syndrome (WAS) is an X-linked disorder characterized by eczema, thrombocytopenia and increased susceptibility of infections, with mutations of the WAS gene being responsible for WAS and X-linked thrombocytopenia. Herein, two novel mutations of WAS at T336C on exon 3, and at 1326-1329, a G deletion on exon 10, resulting in L101P missense mutation and frameshift mutation 444 stop, respectively, are reported. The affected patients with either mutation showed severe suppression of WAS protein (WASP) levels, T cell proliferation, and CFSE-labeled T cells division. Because WASP L101 have not shown direct nuclear Overhauser effect (NOE) contact with the WASP-interacting protein (WIP) in NMR spectroscopy, molecular modeling was performed to evaluate the molecular effect of WASP P101 to WIP peptide. It is presumed that P101 induced a conformational change in the Q99 residue of WASP and made the side chain of Q99 move away from the WIP peptide, resulting in disruption of the hydrogen bond between Q99 WASP and Y475 WIP. A possible model for the molecular pathogenesis of WAS has been proposed by analyzing the interactions of WASP and WIP using a molecular modeling study.
Department of Pediatrics, Yonsei University College of Medicine, 134 Shinchon-dong Seodaemoon-gu, Seoul 120-752, South Korea.
Moon Kyu
MK
Kim
Eun Sook
ES
Kim
Dong Soo
DS
Kim
In-Hong
IH
Choi
Taesung
T
Moon
Chang No
CN
Yoon
Jeon-Soo
JS
Shin
D000595:Amino Acid Sequence; D001483:Base Sequence; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics*; D002455:Cell Division; D041321:Chromosomes, Human, X; D003598:Cytoskeletal Proteins; D004252:DNA Mutational Analysis; D005091:Exons; D005260:Female; D016368:Frameshift Mutation; D017353:Gene Deletion; D006801:Humans; D006860:Hydrogen Bonding; D007293:Inosine Triphosphate / Q000235:genetics; D047908:Intracellular Signaling Peptides and Proteins; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D020125:Mutation, Missense; D010375:Pedigree; D010455:Peptides / Q000737:chemistry; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry* / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D013601:T-Lymphocytes / Q000378:metabolism; D014923:Wiskott-Aldrich Syndrome / Q000235:genetics*; D051316:Wiskott-Aldrich Syndrome Protein
D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D047908:Intracellular Signaling Peptides and Proteins; D010455:Peptides; D011506:Proteins; C495767:WAS protein, human; C109903:WIPF1 protein, human; D051316:Wiskott-Aldrich Syndrome Protein; D007293:Inosine Triphosphate