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481.
OSF-1 (also known as pleiotrophin, HB-GAM, HBGF-8 or HBNF) is a heparin-binding, neurotrophic protein. Its tissue-specific expression in rats is developmentally regulated and the protein is highly conserved between species. The protein is believed to be involved in neuronal development. Previous experiments in our laboratory showed that OSF-1 is primarily expressed in brain and bone. The biological function of OSF-1 in bone is unknown. In order to overcome the limited availability of the native protein, we now report on the high-level expression of human OSF-1 in Escherichia coli. The protein is present in the form of inclusion bodies, which were isolated and solubilized. The partially purified protein was refolded and further purified employing heparin sepharose chromatography. N-terminal sequence determination revealed the same amino acid sequence as the natural mature protein. The isolated backfolded recombinant human OSF-1 did promote neurites outgrowth in primary cultures of cortical neurons.  相似文献   
482.
In human cervical epithelium, uterine endometrium, and mucosa of the fallopian tubes, neutral glycosphingolipids were exclusively represented by the globo-series glycosphingolipids, such as CMH, LacCer, Gb3Cer and Gb4Cer, but the molecular species of their ceramide moieties were characteristically altered in the cervical epithelium and uterine endometrium during the menstrual cycle. Individual neutral glycosphingolipids in the cervical epithelium and the uterine endometrium at the follicular phase gave two bands on TLC, whereas those at the luteal phase displayed three bands, the third being the lower migrating one. Neutral glycosphingolipids migrating to the same positions as these lower-migrating bands were constantly detected in the mucosa of the fallopian tubes, independent of the menstrual cycle. The lower-migrating bands for the cervical epithelium and the uterine endometrium at the luteal phase were due to molecules mainly constructed of phytosphingosine with alpha-hydroxy fatty acids having chain lengths of 18-24 and 4-sphingenine with alpha-hydroxy fatty acids having chain lengths of 16-22, whereas those in the mucosa of the fallopian tubes were exclusively N-alpha-hydroxypalmitoyl 4-sphingenine.  相似文献   
483.
Peptide with C-terminal tyrosine amide was isolated from porcine brain by acid extraction and sequential steps of reverse phase HPLC. Microsequence, amino acid and mass spectral analyses revealed the structure: Ac-Ala-Ser-Glu-Lys-Arg-Pro-Ser-Glu-Arg-His-Gly-Ser-Lys- Tyr-amide. Since this peptide had the identical sequence to N-terminus of porcine myelin basic protein (pMBP) 1-14, we have designated porcine myelin peptide amide 14 (pMPA14). The final HPLC step yielded 20 micrograms of homogeneous peptide preparation from 20 kg brain tissue. Unlike other amidated peptides, pMPA14 may be produced by non enzymatic mechanism or unknown amidating enzyme. This unique amidation seems to occur exclusively to MBP in the brain.  相似文献   
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