Mechanism of 24p3 Protein, Mouse Uterine Secretory Protein Internalizes to L929 Cell Line
Date Issued
2005
Date
2005
Author(s)
Chou, Hsien-Yeh
DOI
zh-TW
Abstract
24p3 protein is a 25.8 kD glycoprotein which belongs to the lipocalin superfamily. It is expressed and secreted from uterine endometrial epithelia during the proestrous phase of female mice, but is constitutively expressed in epididymis. The protein could associate with sperm head and then enhance the sperm motility, but was suggested as a stressor of sperm capacitation and fertility. It was also considered as an apoptotic factor or inflammatory factor in blood cells. The real function is unclear. Our previous studies showed that 24p3 protein could internalize into the cell and had effects on mouse connective tissue cell line, L929.
Lipocalin has been proposed internalizing into the cells via receptor-mediated endocytosis and triggering further signal transduction. The unclearity of the 24p3 protein interacting molecule in cell membrane encouraged us to find out the interacting molecule(s) from the cell. Using L929 cell line as a model, we attempted to demonstrate the unknown interacting protein and transition pathway. The competition assay and endocytosis inhibition studies indicated that 24p3 protein could bind to the cell surface specifically and transport into the cell via receptor-mediated endocytosis pathway. Observation the locations of FITC-LAMP-2 Ab(lysosome- associated membrane protein-2 antibody) and the Alexa555-24p3 protein under fluorescence microscope revealed that the 24p3 protein should be localized in lysosome. The degradation of internalized 24p3 protein in L929 cells coincided with the colocalization of 24p3 and lysosome. Western blotting analysis of L929 cell membrane protein extract with 24p3 protein showed stress-70 protein might be the interacting protein of 24p3 protein in the PVDF membrane. We constructed a 24p3 protein-coupled affinity column to separate several 24p3 protein associated-membrane protein candidates after flow in the L929 cell membrane protein extract. Furthermore, we will identify the interacting protein of 24p3 protein from L929 cell line by the mass spectrum analysis and elucidate the 24p3 protein signal transduction in the cells.
Subjects
子宮分泌蛋白質
24p3蛋白質
L929細胞株
內吞作用
Uterine secretory protein
24p3 protein
L929 cell line
endocytosis
Type
other
File(s)![Thumbnail Image]()
Loading...
Name
ntu-94-R92b46032-1.pdf
Size
23.31 KB
Format
Adobe PDF
Checksum
(MD5):05a73e0cfd1286016c2890be4a0e8651