Sequence analysis of beta 1, 3-galactosyltranferase specific molecular chaperone Cosmc gene coding region in IgA nephropathy patients / 中国组织工程研究

ABSTRACT

BACKGROUND: Pathogenesy of immunoglobulin A nephropathy (IgAN) is not clear up to now. Present research has verified that the key pathogenetic pathway is abnormalities of IgA1 molecular O-glycosylation induced by decrease of β1, 3-galactosyltranferase activity in IgA1 hinge region of IgAN patients. Prophase study by the authors supposed that the key of IgAN O-glycosylation abnormality might be due to the decrease of β1, 3-galactosyltranferase specific molecular protein chaperone Cosmc in B lymphocyte of peripheral blood in IgAN patients.OBJECTIVE: To measure DNA sequence of β1, 3-galactosyltranferase specific molecular chaperone in coding region of Cosmc gene in IgAN patients, and compared with the sequence of Gene Bank.DESIGN: Case-controlled observation.SETTING: Department of Nephrology, West China Hospital, Sichuan University.PARTICIPANTS: Totally 27 IgAN patients and 10 non-IgAN patients were recruited in Department of Nephrology of West China Hospital of Sichuan University from November 2005 to August 2006, and five normal controls were included in this study. All the subjects knew the fact and agreed to participate in the experiment.METHODS: The experiment was performed at the State Key Laboratory of Biotherapy of Sichuan University. 2 mL peripheral venous blood of all the samples were taken into heparin sodium anticoagulated tubes, from which total genomic DNA were extracted by phenol/chloroform precipitation method. Concentration of DNA was determined by ultraviolet spectrophotometer. The polymerase chain reaction (PCR) was used to amplify the coding region of β1, 3-galactosyltranferase specific molecular chaperone Cosmc gene in all the subjects and direct sequencing was done in PCR products of each subjects. The results of all the sequencing were compared with Gene Bank one by one.MAIN OUTCOME MEASURES: Amplification findings and sequencing of coding region of β1, 3-galactosyltranferase specific molecular chaperone Cosmc gene by PCR.RESULTS: ①Coding region of Cosmc gene located at 257-1 213, and amplified Cosmc gene was 1 247 bp. ②The sequence of Cosmc gene coding region was similar in IgAN patients, non-IgAN patients and normal controls, and no difference of gene sequence was noticed in all the result sequences as compared with the Gene Bank registered sequence.CONCLUSION: No abnormal sequence is found in coding region of Cosmc gene in IgAN patients, suggesting that this coding region probably is not associated with the abnormalities of IgA1 O-glycosylation in IgAN.