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E Herbert

Publications and source records attributed to E Herbert.

At least 73 records · Page 4Linked to original sources
PubMed1982

Partial characterization of the mRNA that codes for enkephalins in bovine adrenal medulla and human pheochromocytoma.

[Met]enkephalin and [Leu]enkephalin are derived from a protein in bovine adrenal medulla that contains multiple copies of [Met]enkephalin [Kilpatrick, D. L., Taniguchi, T., Jones, B. N., Stern, A. S., Shively, J. E., Hullihan, J., Kimura, S., Stein, S. & Udenfriend, S. (1981) Proc. Natl. Acad. Sci. USA 78, 3265--3268.] Here we characterize pro-enkephalin mRNA from bovine and human tissue by use of an oligodeoxynucleotide pentadecamer probe complementary to codons for Tyr-Gly-Gly-Phe-Met ([Met]enkephalin). This probe hybridizes specifically to a species of poly(A)-RNA from adrenal medulla and human pheochromocytoma, (1400--1450 bases), and also to [Met]enkephalin-containing pro-opiomelanocortin mRNAs from bovine pituitary (1200 bases) and from mouse pituitary tumor cell (1100 bases). A cloned cDNA probe (144 bases) complementary to the region of pro-opiomelanocortin mRNA that codes for lipotropin does not hybridize to the RNA from bovine adrenal medulla, demonstrating that the latter RNA is not pro-opiomelanocortin mRNA. The pentadecamer probe was extended to make cDNA with reverse transcriptase after hybridizing it to adrenal poly(A)-RNA. The sequence of an extended cDNA, 62 bases in length, was found to correspond exactly to that expected from the amino acid sequence of peptide E (a bovine adrenal peptide containing [Met]- and [Leu]enkephalin sequences). This cDNA also forms a specific hybrid with the RNA from bovine adrenal and human pheochromocytoma, confirming that these species of RNA are pro-enkephalin mRNA.

Adrenal Gland Neoplasms↗
PubMed1981

Evidence for a signal sequence at the N terminus of the common precursor to adrenocorticothrophin and beta-lipotropin in mouse pituitary cells.

The precursor to corticotropin and beta-endorphin was synthesized in a reticulocyte cell-free system under the direction of mRNA from mouse AtT-20 pituitary tumor cells in the presence of [3H]proline, [3H]phenylalanine, [3H]leucine, [3H]valine, [3H]isoleucine or [35S]methionine. Automatic Edman degradation of the radioactive cell-free product showed the following N-terminal sequence: Pro-1, Met-2, Leu-11, Leu-12, Leu-13, Leu-15, Leu-16, Leu-17, Ile-21 and Val-23. The corticotropin-endorphin precursor was also labeled in AtT-20 cells with [3H]valine, [3H]leucine, [3H]tryptophan, [3H]serine, [35S]methionine or [35S]cysteine. Automatic Edman degradation of the radioactive intact cell form gave the following N-terminal sequence: Trp-1, Cys-2, Leu-3, Ser-5, Ser-6, Val-7, Cys-8, Leu-11, Leu-17, Leu-18 and tentatively Met-27. The sequence of the intact cell form from AtT-20 cells matches the sequence of the cell-free form of bovine pituitary precursor beginning at Trp-27, as determined by recombinant DNA technology [Nakanishi, S., Inoue, A., Kita, T., Nakamura, M., Chang, A. C. Y., Cohen, S. N., and Numa, S. (1979) Nature (Lond.) 278, 423-427]. The sequence of the mouse pituitary mRNA-directed cell-free translation product also matches the bovine precursor beginning at Pro-2. The results suggest that both the mouse and bovine precursors possess a signal sequence of 26 amino acids which is cleaved in intact cells. CNBr cleavage of [35S]cysteine-labelled intact cell precursor gave rise to an N-terminal fragment of a size compatible with the presence of a methionyl residue at or near position 27.

Adrenocorticotropic Hormone↗
PubMed1980

The distribution of forms of adrenocorticotropin and beta-endorphin in normal, tumorous, and autopsy human anterior pituiary tissue: virtual absence of 13K adrenocorticotropin.

To begin to define the nature of the biosynthesis and processing of ACTH and beta-endorphin in the human, anterior pituitary tissue (fresh normal and adenomatous, and autopsy) was extracted in acetic acid in the presence of protease inhibitors and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The gel slice eluates were assayed for ACTH and beta-endorphin immunoactivity. Human anterior pituitary tissue contained four major size classes of ACTH and three major size classes of beta-endorphin. We found that in all tissue sources examined there was a virtual absence of 13-15K ACTH, which is a major form in the rat and mouse. When comparing extracts obtained from fresh normal or adenomatous anterior pituitary tissue, we also found a drastic decrease in beta-lipotropin and beta-endorphin in extracts of autopsy human anterior pituitaries. These results suggest that the biosynthesis and processing of pituitary ACTH and beta-endorphin in the human may be different than in the mouse, and because of apparent postmortem proteolysis of beta-endorphin, human pituitary obtained at autopsy is probably not a good source of material for biochemical studies of pituitary tissue.

Adenoma↗
PubMed1980

A cellular basis for the differences in regulation of synthesis and secretion of ACTH/endorphin peptides in anterior and intermediate lobes of the pituitary.

The focus of research in our laboratory over the past few years has been the regulation of synthesis, processing and release of the ACTH/LPH family of peptides. These peptides are derived from a common precursor protein that is found in both the anterior and intermediate lobes of the pituitary (Roberts et al. 1978) and in the hypothalamus (Liotta et al. 1979). In the anterior lobe this protein gives rise to alpha (1-39)ACTH, beta-lipotropin and an N-terminal fragment of undefined function. In addition, a variety of intermediate lobe pituitary peptides can be derived from the precursor by further processing of ACTH and beta-LPH. In this paper we compare the structure of the precursor in the anterior and intermediate lobes of mouse and rat pituitary. Processing of the precursor to its constituent hormones is then contrasted in primary cultures of anterior and intermediate lobe cells using pulse label and pulse chase techniques with radioactive amino acids and sugars. Finally, we discuss the difference in behaviour of anterior and intermediate lobe cells in culture with regard to their rates of secretion and intracellular turnover of hormones and regulation of these processes by hypothalamic factors, glucocorticoids and catecholamines.

Adrenocorticotropic Hormone↗
PubMed1979

Corticotropin and beta-endorphin: construction and analysis of recombinant DNA complementary to mRNA for the common precursor.

A cDNA fragment synthesized from mouse mRNA (ACTH/LPH mRNA) that codes for the precursor polypeptide containing corticotropin (ACTH), beta-lipotropin (LPH), and several other peptides has been cloned in bacteria. The mRNA was enriched for ACTH/LPH mRNA translational activity (to about 75%) prior to cDNA synthesis. It appears to contain about 1200 bases, of which approximately 450 bases are not translated. The cloned DNA fragment is complementary to the region of the mRNA coding for the protein fragment beta-LPH-(44--90); this contains all of the amino acids of [Met]-enkephalin (residues 61--65 of beta-LPH), most of the amino acids of beta-melanocyte-stimulating hormone, and all but the carboxy-terminal amino acid of beta-endorphin. Based on assignment of the amino acid sequence of mouse beta-LPH from the nucelic acid sequence, it appears that there is extensive homology of mouse beta-LPH with human and porcine beta-LPH. The data also establish the linkage between beta-melanocyte-stimulating hormone and beta-endorphin as a Lys-Arg sequence. It is hoped that this cloned DNA can be used as a probe to study the expression and structure of the ACTH/LPH gene.

Adrenocorticotropic Hormone↗