Molecular Human Reproduction Vol. 1, NUMBER 8 pp. 374-380, 1995
© European Society of Human Reproduction and Embryology 1995
research-article |
Human endometrial proteins with cyclic changes in the expression during the normal menstrual cycle: characterization by protein sequence analysis
1Center for Clinical and Basic Research Ballerup Byvej 222, DK-2750 Ballerup 2Institute of Medical Microbiology and Institute of Human Genetics Aarhus University, DK-8000 Aarhus, Denmark
To whom correspondence should be addressed at: 3To whom correspondence should be addressed
Endometrial proteins showing cyclic expression during the normal menstrual cycle were localized on two-dimensional (2-D) electrophoresis gels separating proteins with isoelectric points (pl) ranging from 3.5 to 7 and relative molecular weights ranging from 10 to 300 kDa. Menstrual cycle-related proteins were excised from several 2-D gels, concentrated by one-dimensional (1-D) sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis, and cleaved in situ by trypsin. The tryptic fragments were extracted and separated by reverse phase high performance liquid chromatography (RP-HPLC). Finally, the partial amino-terminal amino acid sequence of selected tryptic fragments were determined for each protein. We aimed at characterizing the 21 menstrual cycle-related proteins that were visible on silver-stained 2-D electrophoresis gels. Of the proteins being maximally synthesized in the proliferative phase endometrium, we identified proteins associated mainly with the cytoskeleton: vimentins, keratin, tropomyosin and tubulin, but also proteins such as proliferating cell nuclear antigen and ß-galactoside binding lectin. The partial amino acid sequences for another two proteins did not match any protein sequence in the Protein Identification Resource (PIR) and Swissprot databases. In the group of proteins having maximal synthesis in the secretory phase endometrium, we identified creatine kinase chain B and an isocrtrate dehydrogenase-homologous protein, both of which are involved in energy metabolism. However, we also identified the annexin IV precursor, the 14–3–3 protein homologue also called stratrfin or the epithelial cell marker protein 1 and the 21K tumour protein. Finally, four of the proteins were present in too low amounts to allow characterization. Interestingly, most of the identified proteins have not previously been described as having a menstrual cycle-related synthesis in the human endometrium. It may be considered that the concentration of some of the cycle-related proteins may be used in clinical situations to reflect specific endometrial phases.
endometrium/menstrual cycle/proteins/sequence/two-dimensional gel electrophoresis