Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A gene for somatostatin, a mammalian peptide (14 amino acid residues) hormone, was synthesized by chemical methods. This gene was fused to the Escherichia coli beta-galactosidase gene on the plasmid pBR322. Transformation of E. coli with the chimeric plasmid DNA led to the synthesis of a polypeptide including the sequence of amino acids corresponding to somatostatin. In vitro, active somatostatin was specifically cleaved from the large chimeric protein by treatment with cyanogen bromide. This represents the first synthesis of a functional polypeptide product from a gene of chemically synthesized origin.
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PMID:Expression in Escherichia coli of a chemically synthesized gene for the hormone somatostatin. 41 51

Somatostatin gene fragment extracted and purified from plasmid pSom5 bacterium was ligated with the plasmid pBD2 DNA. Transformation of E. coli D29A1 with the chimeric plasmid DNA led to the synthesis of a polypeptide including the sequence of amino acids corresponding to somatostatin. The chimeric protein (50000 dalton) was purified and characterized by the beta-galactosidase affinity chromatography and the expression of the somatostatin gene in E. coli D29A1 is certain after the radioimmunoassay of the chimeric protein and its mixture by treatment with cyanogen bromide.
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PMID:[Expression of somatostatin gene in E. coli D29A1]. 167 42

The targeting of tumor cells by peptides for drug delivery is a promising strategy for cancer therapy. Interleukin-2 (IL-2), which mediates anti-tumor cellular immune responses, has been approved as a therapy for cancer. However, the serious side effects and short half-life of recombinant IL-2 (rIL-2) has limited its use clinically. Somatostatin receptors (SSTRs), which are expressed in a large number of human tumors, are the targets for in vivo tumor targeting. In this study, we have constructed and expressed a novel chimeric recombinant protein containing octreotide analogs and IL-2 in order to target the SSTR binding with tumor cells. The fusion protein somatostatin receptor targeted interleukin-2 (SIL), which was purified from bacterial inclusion bodies and refolded with high purity, was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and reverse-phase high-performance liquid chromatography. Tryptophan emission fluorescence was used to measure the structural changes in SIL after renaturation. Cell proliferation experiments showed that this chimeric protein retained the biological activities of hIL-2. Furthermore, the tumor binding capacity of SIL acting through SSTRs was shown through co-immunoprecipitation. Competition binding with octreotide of tumor cells also confirmed that SIL binds to tumor cells through the target peptide octreotide. Moreover, the performance of SIL in stimulating the proliferation of lymphocyte cell lines after binding to tumor cells showed that the immunocytokine, SIL, retained its bioactivity at the tumor site. These results suggest that SIL is a recombinant fusion protein that may be used for tumor-targeted drug delivery.
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PMID:Expression, purification, refolding, and characterization of octreotide-interleukin-2: a chimeric tumor-targeting protein. 2168 29