Research

Studies on substantially increased proteins in follicular fluid of bovine ovarian follicular cysts using 2-D PAGE and MALDI-TOF MS

Jiro Maniwa^1,2 , Shunsuke Izumi³ , Naoki Isobe¹ and Takato Terada¹

¹Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8528, Japan

²Preclinical Sciences Department, AstraZeneca KK, Osaka 531-0076, Japan

³Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526, Japan

author email corresponding author email

Reproductive Biology and Endocrinology 2005, 3:23doi:10.1186/1477-7827-3-23

Published:	8 June 2005

Abstract

Background

The objective of this study was to identify substantially increased proteins in bovine cystic follicular fluid (FF) in order to clarify the pathology and etiology of bovine ovarian follicular cysts (BOFC).

Methods

Proteins in normal and cystic FF samples were subjected to two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) and were compared using silver stained gel images with PDQuest image analysis software. Peptides from these increased spots were analyzed by matrix assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS), and were identified based on the NCBI database by a peptide mass fingerprinting method.

Results

Comparative proteomic analysis showed 8 increased protein spots present in cystic FF. MS analysis and database searching revealed that the increased proteins in cystic FF were bovine mitochondrial f1-atpase (BMFA), erythroid associated factor (EAF), methionine synthase (MeS), VEGF-receptor, glyceraldehydes 3-phosphate dehydrogenase (GAPDH), heat shock protein 70 (HSP70), β-lactoglobulin (BLG) and succinate dehydrogenase Ip subunit (SD).

Conclusion

Our results suggest that these proteins are overexpressed in BOFC, and that they may play important roles in the pathogenesis of BOFC. Furthermore, these proteins in the FF could be useful biomarkers for BOFC.