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.
Park
Hyo-Jin
HJ
Research Institute of Molecular Genetics, Catholic Research Institutes of Medical Sciences, College of Medicine, the Catholic University of Korea, Seoul 137-701, Korea.
Choi
Ju-Youn
JY
Seong
Young-Mo
YM
Han
Chul
C
Yoon
Sung-Joo Kim
SJ
Kang
Seongman
S
Rhim
Hyangshuk
H
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