Ghrelin, a novel growth-hormone-releasing acylated peptide, synthesized in a distinct endocrince cell type in rats and humans

ABSTRACT Cultured 3T3-F442A preadipocytes are able to undergo GH-promoted differentiation into adipocytes. The relationship between the structure and function of GH receptors on 3T3 cells (3T3-F442A preadipocytes, differentiated adipocytes and 3T3-C2 cells, which vary in susceptibility to adipose conversion or with respect to carbohydrate and lipid metabolism) was studied by the covalent cross-linking of 125I-labelled human (h) GH to intact cells with the bifunctional reagent disuccinimidyl suberate. When preadipocytes were cross-linked and analysed using sodium dodecylsulphate-polyacrylamide gel electrophoresis, a prominent 125I-labelled hGH-receptor complex of Mr 130 000 was observed along with minor complexes (Mr 300 000, 230 000 and 60 000) on autoradiography. Non-reducing—reducing two-dimensional gel electrophoresis revealed that the higher molecular weight complexes also contained the Mr 130 000 complex. Neuraminidase and tunicamycin treatment demonstrated that the GH receptor on F442A preadipocytes is a sialo-glycoprotein with N-linked carbohydrate chains. When the differentiated 3T3-F442A adipocytes and 3T3-C2 cells (a sub-line with no susceptibility to adipose conversion with GH) were examined in the same way as 3T3-F442A preadipocytes, no differences were observed in the specificity of GH binding and in the molecular size of the 125I-labelled hGH-receptor complexes and their glycosylation characteristics. This suggests that the structural characteristics of the GH receptor are closely related in each cell type, but that the hormonal signals produced after GH binding to the receptor may cause different effects according to the cell type.

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Cell Type Specific Expression of the Growth Hormone Gene and its Control by GHF-1

Folia Endocrinologica Japonica ◽

10.1507/endocrine1927.66.12_1205 ◽

1990 ◽

Vol 66 (12) ◽

pp. 1205-1220

Author(s):

Michael Karin ◽

Lars Theill ◽

Jose-Luis Castrillo ◽

Alison McCormick ◽

Helen Brady

Keyword(s):

Growth Hormone ◽

Growth Hormone Gene ◽

Cell Type ◽

Specific Expression ◽

Cell Type Specific Expression ◽

Cell Type Specific

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Ghrelin is a growth-hormone-releasing acylated peptide from stomach

Nature ◽

10.1038/45230 ◽

1999 ◽

Vol 402 (6762) ◽

pp. 656-660 ◽

Cited By ~ 5419

Author(s):

Masayasu Kojima ◽

Hiroshi Hosoda ◽

Yukari Date ◽

Masamitsu Nakazato ◽

Hisayuki Matsuo ◽

...

Keyword(s):

Growth Hormone ◽

Acylated Peptide

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Repression mediates cell-type-specific expression of the rat growth hormone gene.

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.83.21.8283 ◽

1986 ◽

Vol 83 (21) ◽

pp. 8283-8287 ◽

Cited By ~ 39

Author(s):

P. R. Larsen ◽

J. W. Harney ◽

D. D. Moore

Keyword(s):

Growth Hormone ◽

Growth Hormone Gene ◽

Cell Type ◽

Specific Expression ◽

Cell Type Specific Expression ◽

Rat Growth ◽

Cell Type Specific

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Adipocytes may not be a terminally differentiated cell type: implications for animal production

Animal Science ◽

10.1017/s1357729805000275 ◽

2005 ◽

Vol 80 (3) ◽

pp. 239-240 ◽

Cited By ~ 16

Author(s):

M.V. Dodson ◽

M.E. Fernyhough ◽

J.L. Vierck ◽

G.J. Hausman

Keyword(s):

Cell Cycle ◽

Growth Hormone ◽

Lipid A ◽

Fat Cells ◽

Beef Steers ◽

Cell Type ◽

Animal Science ◽

Direct Function ◽

Cell Form ◽

Fat Depot

Mature adipocytes may not be a terminally differentiated cell form, as previously thought by about everyone in science. Instead, these adipocytes may be capable of re-entering the cell cycle and forming proliferative-competent precursor cells like preadipocytes, adipofibroblasts, or even other forms of cells. Why is this possibility important to animal science? The main reason is in directing the cellularity of adipocyte depots in meat animals. For example, we know that the fat characteristics of beef animals are a direct function of the ‘cellularity’ of cells committed to form adipocytes. Beef steers given a high-concentrate diet commonly possess fewer adipocytes in any given fat depot, but most of the cells are completely filled with lipid to capacity. Alternatively, steers on a high-roughage diet seem to possess more fat cells, but fewer of them are filled to capacity with storage lipid. A variety of systemic and local regulators have been implicated in altering the cellularity of any given fat depot. Major regulators appear to be growth hormone, any number of repartitioning agents, as well as adipocytokines produced by the cells within the fat depot themselves. The specific mechanisms involved in directing cellularity of any specific fat depot, however, are poorly understood.

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Studies with fluorescein-conjugated antisera to growth hormones. III. Localization and inhibition studies with antisera to porcine growth hormone

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y70-006 ◽

1970 ◽

Vol 48 (1) ◽

pp. 39-42 ◽

Cited By ~ 2

Author(s):

R. Nayak ◽

Eleanor E. McGarry ◽

J. C. Beck

Keyword(s):

Growth Hormone ◽

Growth Hormones ◽

Cell Type ◽

Orange G ◽

Inhibition Studies

Fluorescein-conjugated antisera to porcine growth hormone localize in acidophils of rat, pig, beef, sheep, and dog pituitaries. Using AT – PAS – orange G stain, two types of acidophils could be distinguished in pig, beef, sheep, and dog pituitaries. Localization of anti-porcine growth hormone was confined to only one acidophil cell type in pituitaries of these species.

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