Antigenicity of the region encoded by exon8 of the human serine protease, HtrA2/Omi, is associated with its protein solubility.
HtrA2/Omi, a mitochondrial serine protease, is pivotal in regulating apoptotic cell death. To determine the location of antigenic determinants in HtrA2/Omi, we expressed a series of the N-terminally truncated HtrA2/Omi as GST fusion proteins in E. coli. We assessed protein solubility and antigenic reactivity of various N-terminally truncated HtrA2/Omi proteins by binding to glutathione beads and immunoblot analyses, respectively. We identified that the region encoded by exon8 of HtrA2/Omi was expressed as a highly soluble form and contains an antigenic determinant specifically recognized by a polyclonal serum against HtrA2/Omi. Our data provide evidence that protein solubility of the specific region in target proteins may contribute to the antigenicity.
Research Institute of Molecular Genetics, Catholic Research Institutes of Medical Sciences, College of Medicine, the Catholic University of Korea, Seoul 137-701, Korea.
Hyo-Jin
HJ
Park
Ju-Youn
JY
Choi
Young-Mo
YM
Seong
Chul
C
Han
Sung-Joo Kim
SJ
Yoon
Seongman
S
Kang
Hyangshuk
H
Rhim
D000939:Epitopes / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D005091:Exons / Q000235:genetics; D000074923:High-Temperature Requirement A Serine Peptidase 2; D006801:Humans; D024101:Mitochondrial Proteins; D011993:Recombinant Fusion Proteins / Q000276:immunology / Q000378:metabolism; D020539:Sequence Analysis, Protein; D012697:Serine Endopeptidases / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D012710:Serum Albumin, Bovine / Q000378:metabolism; D012995:Solubility; D013329:Structure-Activity Relationship
D000939:Epitopes; D024101:Mitochondrial Proteins; D011993:Recombinant Fusion Proteins; D012710:Serum Albumin, Bovine; D012697:Serine Endopeptidases; C000615914:HTRA2 protein, human; D000074923:High-Temperature Requirement A Serine Peptidase 2