1
|
Zhang X, Shao S, Zhao L, Yang R, Zhao M, Fang L, Li M, Chen W, Song Y, Xu C, Zhou X, Zhao J, Gao L. ER stress contributes to high-fat diet-induced decrease of thyroglobulin and hypothyroidism. Am J Physiol Endocrinol Metab 2019; 316:E510-E518. [PMID: 30620634 DOI: 10.1152/ajpendo.00194.2018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Recent studies revealed the emerging role of excess uptake of lipids in the development of hypothyroidism. However, the underlying mechanism is largely unknown. We investigated the effect of high-fat diet (HFD) on thyroid function and the role of endoplasmic reticulum (ER) in HFD-induced hypothyroidism. Male Sprague-Dawley rats were fed with HFD or control diet for 18 wk. HFD rats showed an impaired thyroid function, with decreased thyroglobulin (Tg) level. We found the ER stress was triggered in HFD rat thyroid glands and palmitate-treated thyrocytes. Luminal swelling of ER in thyroid epithelial cells of HFD rats was also observed. The rate of Tg degradation increased in palmitate-treated thyrocytes. In addition, applying 4-phenyl butyric acid to alleviate ER stress in HFD rats improved the decrease of Tg and thyroid function. Withdrawal of the HFD improved thyroid function . In conclusion, we demonstrate that ER stress mediates the HFD-induced hypothyroidism, probably by impairing the production of Tg, and attenuation of ER stress improves thyroid function. Our study provides the understanding of how HFD induces hypothyroidism.
Collapse
Affiliation(s)
- Xiaohan Zhang
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University , Shandong , China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
| | - Shanshan Shao
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University , Shandong , China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
| | - Lifang Zhao
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University , Shandong , China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
| | - Rui Yang
- Experimental Animal Center, Shandong Provincial Hospital Affiliated to Shandong University, Ji-nan, Shandong , China
| | - Meng Zhao
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University , Shandong , China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
| | - Li Fang
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University , Shandong , China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
| | - Mengzhu Li
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University , Shandong , China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
| | - Wenbin Chen
- Scientific Center, Shandong Provincial Hospital Affiliated to Shandong University, Ji-nan, Shandong , China
| | - Yongfeng Song
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University , Shandong , China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
| | - Chao Xu
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University , Shandong , China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
| | - Xiaoming Zhou
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University , Shandong , China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
| | - Jiajun Zhao
- Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University , Shandong , China
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
| | - Ling Gao
- Shandong Provincial Key Laboratory of Endocrinology and Lipid Metabolism, Ji-nan, Shandong , China
- Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji-nan, Shandong , China
- Scientific Center, Shandong Provincial Hospital Affiliated to Shandong University, Ji-nan, Shandong , China
| |
Collapse
|
2
|
Abstract
1. RNA was isolated from crude nuclear preparations and from ribosomes derived from rat brain and liver. Nuclear RNA was obtained by lysis of the nuclei with sodium dodecyl sulphate, followed by denaturation and removal of DNA and protein with hot phenol. 2. Base composition analyses indicated that the cerebral nuclear RNA preparation contained a higher proportion of non-ribosomal RNA than the analogous hepatic preparation. 3. Sucrose-density-gradient analyses revealed a heterogeneous profile for each nuclear RNA preparation, with two major peaks possessing the sedimentation properties of ribosomal RNA (18s and 28s). 4. Template activities of both preparations were widely distributed through the sucrose density gradients. 5. The cerebral nuclear RNA preparation was more active than the hepatic nuclear RNA preparation in promoting amino acid incorporation in cell-free systems from Escherichia coli and rat brain. 6. Cerebral nuclear RNA stimulated amino acid incorporation in a cerebral ribosomal system even in the presence of an excess of purified E. coli transfer RNA. 7. It is concluded that a significant proportion of cerebral nuclear RNA has the characteristics of messenger RNA.
Collapse
Affiliation(s)
- S C Bondy
- Department of Biological Chemistry, School of Medicine and the Brain Research Institute, University of California Center for Health Sciences, Los Angeles, Calif. 90024, U.S.A
| | | |
Collapse
|
3
|
Arvan P, Kim PS, Kuliawat R, Prabakaran D, Muresan Z, Yoo SE, Abu Hossain S. Intracellular protein transport to the thyrocyte plasma membrane: potential implications for thyroid physiology. Thyroid 1997; 7:89-105. [PMID: 9086577 DOI: 10.1089/thy.1997.7.89] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We present a snapshot of developments in epithelial biology that may prove helpful in understanding cellular aspects of the machinery designed for the synthesis of thyroid hormones on the thyroglobulin precursor. The functional unit of the thyroid gland is the follicle, delimited by a monolayer of thyrocytes. Like the cells of most simple epithelia, thyrocytes exhibit specialization of the cell surface that confronts two different extracellular environments-apical and basolateral, which are separated by tight junctions. Specifically, the basolateral domain faces the interstitium/bloodstream, while the apical domain is in contact with the lumen that is the primary target for newly synthesized thyroglobulin secretion and also serves as a storage depot for previously secreted protein. Thyrocytes use their polarity in several important ways, such as for maintaining basolaterally located iodide uptake and T4 deiodination, as well apically located iodide efflux and iodination machinery. The mechanisms by which this organization is established, fall in large part under the more general cell biological problem of intracellular sorting and trafficking of different proteins en route to the cell surface. Nearly all exportable proteins begin their biological life after synthesis in an intracellular compartment known as the endoplasmic reticulum (ER), upon which different degrees of difficulty may be encountered during nascent polypeptide folding and initial export to the Golgi complex. In these initial stages, ER molecular chaperones can assist in monitoring protein folding and export while themselves remaining as resident proteins of the thyroid ER. After export from the ER, most subsequent sorting for protein delivery to apical or basolateral surfaces of thyrocytes occurs within another specialized intracellular compartment known as the trans-Golgi network. Targeting information encoded in secretory proteins and plasma membrane proteins can be exposed or buried at different stages along the export pathway, which is likely to account for sorting and specific delivery of different newly-synthesized proteins. Defects in either burying or exposing these structural signals, and consequent abnormalities in protein transport, may contribute to different thyroid pathologies.
Collapse
Affiliation(s)
- P Arvan
- Division of Endocrinology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
| | | | | | | | | | | | | |
Collapse
|
4
|
HARRIS H, SABATH LD. INDUCED ENZYME SYNTHESIS IN THE ABSENCE OF CONCOMITANT RIBONUCLEIC ACID SYNTHESIS. Nature 1996; 202:1078-80. [PMID: 14207198 DOI: 10.1038/2021078a0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
5
|
|
6
|
|
7
|
Dinsart C, Van Voorthuizen F, Vassart G. Reverse transcription of thyroglobulin 33-S mRNA. EUROPEAN JOURNAL OF BIOCHEMISTRY 1977; 78:175-81. [PMID: 71991 DOI: 10.1111/j.1432-1033.1977.tb11727.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Bovine thyroglobulin 33-S mRNA has been used as a template for the synthesis of a complementary DNA, using RNA-directed DNA polymerase from the avian myeloblastosis virus. The yield of the reaction was relatively poor and the size of the cDNA did not exceed 10 S. Nevertheless, a copy of high specific radioactivity (approximately 10(7) counts. min-1 microgram-1) could be obtained which hybridized specifically back to its template with an rot1/2 value about 5 times higher than that observed in hybridizations between hemoglobin mRNA (alpha + beta chain) and hemoglobin cDNA. This suggests that thyroglobulin mRNA does not contain extensive internal repetitive sequences. Quantification of thyroglobulin mRNA sequences among various RNA preparations from the beef thyroid was performed using cDNA/RNA hybridizations in RNA excess. The results confirmed that thyroglobulin mRNA represents the large majority of mRNA in membrane-bound polysomes and indicated the virtual absence of thyroglobulin sequences on free polyosomes. The cDNA transcribed from mRNA of bovine origin hybridized efficiently with thyroid RNA from goats, dogs and humans. Although the heterologuous hybrids exhibited the expected decrease in thermal stability, the bovine cDNA provides an appropriate probe for studies dealing with the expression of the thyroglobulin gene in various mammals including man.
Collapse
|
8
|
Chebath J, Chabaud O, Becarevic A, Cartouzou G, Lissitzky S. Thyroglobulin messenger ribonucleic acid translation in vitro. EUROPEAN JOURNAL OF BIOCHEMISTRY 1977; 77:243-52. [PMID: 891532 DOI: 10.1111/j.1432-1033.1977.tb11663.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
9
|
De Nayer P, Caucheteux D, Luypaert B. Identification of RNA species with messenger activity in the thyroid gland. FEBS Lett 1977; 76:316-9. [PMID: 862912 DOI: 10.1016/0014-5793(77)80176-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
10
|
|
11
|
Vassart G, Refetoff S, Brocas H, Dinsart C, Dumont JE. Translation of thyroglobulin 33S messenger RNA as a means of determining thyroglobulin quaternary structure. Proc Natl Acad Sci U S A 1975; 72:3839-43. [PMID: 1060067 PMCID: PMC433091 DOI: 10.1073/pnas.72.10.3839] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Thyroglobulin is a 19S protein of approximately 660,000 daltons and unknown quaternary structure. We have previously shown that a 33S mRNA purified from mammalian thyroids promoted synthesis in the Xenopus oocyte of a peptide immunologically related to thyroglobulin. Chemical identity to the native protein is now presented by means of a tryptic peptide analysis. Moreover, the 33S mRNA is shown to contain all the information required for the synthesis of a complete 19S thyroglobulin molecule. Gel filtration in Sepharose under denaturing conditions indicates that the reduced polypeptide encoded by the 33S mRNA is larger than 210,000 daltons. A model of a dimeric thyroglobulin with about 300,000 dalton subunits is presented.
Collapse
|
12
|
Vassart G, Brocas H, Lecocq R, Dumont JE. Thyroglobulin messenger RNA: translation of a 33-S mRNA into a peptide immunologically related to thyroglobulin. EUROPEAN JOURNAL OF BIOCHEMISTRY 1975; 55:15-22. [PMID: 1236796 DOI: 10.1111/j.1432-1033.1975.tb02133.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Poly(UC)--Sepharose chromatography of the RNA extracted from a thyroid fraction sedimenting between 800 X g and 27000 X g allows the purification of two RNA fractions amounting each to 1% of the applied material. The first one is loosely bound to the column from which it is eluted at 25 degrees C. It is mainly composed of 16-S and 12-S RNA comprising no poly(A) sequences. This could correspond to mitochondrial rRNA. The second one, which is eluted at 50 degrees C, is poly(A)-rich and represents 33-S and 17--18-S RNA species. The 33-S RNA resists heating at 80 degrees C, suggesting that it is composed of one polynucleotide chain. When injected into Xenopus oocytes, the 33-S RNA specifically promotes the synthesis of a peptide with an apparent molecular weight of 185000 and an apparent sedimentation coefficient of 10-S. This peptide is immunologically related to thyroglobulin and could represent its main precursor. Under the conditions tested it does not polymerize spontaneously into 19-S thyroglobulin, suggesting that assembly of the molecule could require specific, post-translational alterations of the precursor and/or the presence of additional lighter subunits.
Collapse
|
13
|
Shires TK, Pitot HC. The membron: a functional hypothesis for the translational regulation of genetic expression. BIOMEMBRANES 1974; 5:81-145. [PMID: 4603228 DOI: 10.1007/978-1-4684-7389-6_3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
14
|
Craig N. The effects of inhibitors of RNA and DNA synthesis on protein synthesis and polysome levels in mouse L-cells. J Cell Physiol 1973; 82:133-50. [PMID: 4543149 DOI: 10.1002/jcp.1040820202] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
15
|
Vassart G, Dumont JE. Identification of polysomes synthesizing thyroglobulin. EUROPEAN JOURNAL OF BIOCHEMISTRY 1973; 32:322-30. [PMID: 4687398 DOI: 10.1111/j.1432-1033.1973.tb02613.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
16
|
Vecchio G, Claar GM, Salvatore G. Biosynthesis of Thyroid Iodoproteins in Vivo and in Tissue Slices. J Biol Chem 1972. [DOI: 10.1016/s0021-9258(19)44997-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
17
|
Weyer J, Bussard AE. Kinetics of antibody production by single cells. II. The action of transcription and translation inhibitors upon the metabolism of haemolysin-secreting cells. Immunol Suppl 1972; 22:943-58. [PMID: 4555780 PMCID: PMC1407887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The plaque-forming cell (PFC) population from spleens of mice at the peak of the primary immune response against sheep red blood cells has been analysed using a plaque-assay technique and automatic photographic equipment which recorded plaque formation and growth within a carboxymethyl-cellulose gel. Preliminary biochemical studies, using tritiated uridine and leucine as markers, and actinomycin D and puromycin as inhibitors of transcription and translation respectively, were performed with normal spleen cells. The effect of each of these inhibitors was then tested by means of the plaque-assay technique. The formation and subsequent growth of a plaque within a normal gel are processes in which both transcription and translation are required for haemolysin secretion. It was found that in PFC populations, the functional lifespan of messenger RNA (m-RNA) specific for haemolysin translation has a mean value of 4 hours, while the functional lifespan of total RNA in whole spleen cell populations is not more than 2 hours. The pool of haemolysin stored in a PFC has a mean secretion time of 1.5 hours. There was considerable heterogeneity with regard to the storage of haemolysin and to the functional lifespan of the haemolysin-specific m-RNA from one PFC to another within the spleen population. Furthermore, some PFC which displayed a high secretion rate of haemolysin were unaffected by actinomycin D, while others were inhibited within a few hours. The short-term action of each inhibitor has been studied. Puromycin was found to have a reversible action on PFC expression, while a 1-hour duration of action of actinomycin D was sufficient to inhibit irreversibly the subsequent PFC expression.
Collapse
|
18
|
Thomson JA. Abnormalities of Thyroglobulin Biosynthesis [ Abridged]. Proc R Soc Med 1972. [DOI: 10.1177/003591577206500528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- J A Thomson
- University Department of Medicine, Royal Infirmary, Glasgow
| |
Collapse
|
19
|
Thomson JA. Abnormalities of thyroglobulin biosynthesis. Proc R Soc Med 1972; 65:491. [PMID: 5083687 PMCID: PMC1643899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
20
|
Feeney L, Wissig SL. A biochemical and radioautographic analysis of protein secretion by thyroid lobes incubated in vitro. J Cell Biol 1972; 53:510-22. [PMID: 4337111 PMCID: PMC2108720 DOI: 10.1083/jcb.53.2.510] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
In this study we analyzed several aspects of protein secretion by thyroid follicular cells. The study was carried out on intact thyroid lobes obtained from newborn rats and incubated in vitro. The fate of leucine-(3)H incorporated into protein within follicular cells of untreated and thyrotropic hormone (TSH)-treated lobes was traced by quantitative electron microscope radioautography. Our findings indicate that protein synthesized by the rough-surfaced endoplasmic reticulum during a pulse exposure to leucine-(3)H is released relatively slowly by this organelle. Approximately 1 hr after onset of the pulse, a peak of radioactive protein appears in the Golgi region. The significance of this peak is not clear. Newly synthesized secretory protein passes through the apex of follicular cells without being concentrated or temporarily stored there in the form of large secretory droplets. Passage probably takes place via small vesicles which are intermingled among diverse small vesicles at the apex of the cells as well as in the Golgi region. Exposure of the lobes to TSH in the incubation medium for 45 or 90 min does not stimulate incorporation of leucine-(3)H into protein. Acute stimulation with TSH does, however, modify the movement of secretory protein within the exocrine secretory apparatus of the follicular cell. It accelerates the arrival of the protein at the apex of follicular cells, and it accelerates the release of the protein into the follicular lumen.
Collapse
|
21
|
Identification and Characterization of Two Labeled Intermediates in the Biosynthesis of Rat Thyroglobulin. J Biol Chem 1971. [DOI: 10.1016/s0021-9258(19)34168-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
22
|
Meltz M, Okada S. Characterization of the rapidly labeled hybridizable RNA synthesized in L5178Y mouse leukemic cells. Hybridization lifetime studies. Biophys J 1971; 11:582-95. [PMID: 5104468 PMCID: PMC1483978 DOI: 10.1016/s0006-3495(71)86237-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
An attempt is made to characterize the rapidly labeled hybridizable RNA of L5178Y mouse leukemic cells which has been shown to have similar base sequences when synthesized in two different stages of the cell cycle. The size of rapidly labeled RNA molecules was heterogeneous. For labeling times of 20 min or less, the per cent of hybridization was maximal. With longer labeling times, the per cent of hybridization decreased as radioactivity appeared in long-lived species of low hybridization efficiency; the radioactivity profile resembled the optical density profile in sucrose gradients. The lifetime of newly synthesized hybridizable RNA was studied by pulse labeling exponentially growing cells and then "chasing" with nonradioactive uridine. The per cent of hybridization was studied as a function of chase time. Three RNA groups, which comprised different proportions of rapidly labeled hybridizable RNA, were distinguished. The short-lived group had a half-life of 10 min, much less than the values reported in the literature for messenger RNA of mammalian cells. The half-life of 1-1(1/2) hr observed for a medium-lived group more closely corresponds to that of messenger RNA. A long-lived group had a half-life of approximately 20 hr. Specific activity measurements during chase indicate the presence of a "pool" of labeled uridine derivatives. The uridine of this pool appears to be nonexchangeable with but dilutable by exogenous uridine. A nontoxic concentration of actinomycin D was added to the chase media in an attempt to block the "pool effect". A rapidly degradable RNA was demonstrable both by specific activity and per cent of hybridization measurements.
Collapse
|
23
|
|
24
|
|
25
|
Whur P, Herscovics A, Leblond CP. Radioautographic visualization of the incorporation of galactose-3H and mannose-3H by rat thyroids in vitro in relation to the stages of thyroglobulin synthesis. J Biophys Biochem Cytol 1969; 43:289-311. [PMID: 5344149 PMCID: PMC2107858 DOI: 10.1083/jcb.43.2.289] [Citation(s) in RCA: 247] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Rat thyroid lobes incubated with mannose-(3)H, galactose-(3)H, or leucine-(3)H, were studied by radioautography. With leucine-(3)H and mannose-(3)H, the grain reaction observed in the light microscope is distributed diffusely over the cells at 5 min, with no reaction over the colloid. Later, the grains are concentrated towards the apex, and colloid reactions begin to appear by 2 hr. With galactose-(3)H, the reaction at 5 min is again restricted to the cells but it consists of clumped grains next to the nucleus. Soon after, grains are concentrated at the cell apex and colloid reactions appear in some follicles as early as 30 min. Puromycin almost totally inhibits incorporation of leucine-(3)H and mannose-(3)H, but has no detectable effect on galactose-(3)H incorporation during the 1st hr. Quantitation of electron microscope radioautographs shows that mannose-(3)H label localizes initially in the rough endoplasmic reticulum, and by 1-2 hr much of this reaction is transferred to the Golgi apparatus. At 3 hr and subsequently, significant reactions are present over apical vesicles and colloid, while the Golgi reaction declines. Label associated with galactose-(3)H localizes initially in the Golgi apparatus and rapidly transfers to the apical vesicles, and then to the colloid. These findings indicate that mannose incorporation into thyroglobulin precursors occurs within the rough endoplasmic reticulum; these precursors then migrate to the Golgi apparatus, where galactose incorporation takes place. The glycoprotein thus formed migrates via the apical vesicles to the colloid.
Collapse
|
26
|
|
27
|
Havemann K. Nucleinsäure- und Proteinstoffwechsel in Lymphocytenkulturen von Gesunden und Patienten mit Erkrankungen des lymphatischen Systems. ACTA ACUST UNITED AC 1969. [DOI: 10.1007/bf02044668] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
28
|
Vecchio G, Carlomagno MS, Claar GM. Biosynthesis of thyroglobulin: Partial characterization of a labeled 6 S precursor. FEBS Lett 1969; 4:323-326. [PMID: 11947214 DOI: 10.1016/0014-5793(69)80266-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- G Vecchio
- Centro di Endocrinologia e Oncologia Sperimentale del C N. R.: Istituto di Patologia generale, university of Naples, Naples, Italy
| | | | | |
Collapse
|
29
|
Herscovics A. Biosynthesis of thyroglobulin. Incorporation of [1-14C] galactose, [1-14C] manose and [4,5-3H2] leucine into soluble proteins by rat thyroids in vitro. Biochem J 1969; 112:709-19. [PMID: 5821729 PMCID: PMC1187775 DOI: 10.1042/bj1120709] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
1. Rat thyroid lobes were incubated for various periods of time in Krebs-Ringer bicarbonate containing [(3)H]leucine and either [1-(14)C]galactose or [1-(14)C]mannose. Radioactivity in soluble proteins was determined after their separation by sucrose-gradient centrifugation. 2. The time-course of incorporation of label from [(14)C]-mannose into soluble thyroid proteins was parallel to that observed for [(3)H]leucine. There was a lag of at least 30min. before either label appeared in non-iodinated thyroglobulin (protein 17-18s). During this time both labels were detected in two fractions known to contain subunit precursors of thyroglobulin (fractions 12s and 3-8s). Radioactivity from double-labelled fractions 12s and 3-8s was transferred to protein 17-18s during subsequent incubation in an unlabelled medium. 3. In contrast, most of the [(14)C]galactose was immediately incorporated into protein 17-18s. 4. During the first hour of incubation, puromycin almost completely inhibited the incorporation of label from [(3)H]leucine and [(14)C]mannose into all protein fractions, but had little effect on the incorporation of [(14)C]galactose into protein 17-18s. 5. These results indicate that mannose is incorporated into the carbohydrate groups of protein 17-18s at an earlier stage in its formation than galactose. It is suggested that the synthesis of the carbohydrate groups of ghyroglobulin begins soon after formation of the polypeptide components, more than 30min. before these are aggregated to protein 17-18s; carbohydrate synthesis then proceeds in a stepwise manner, galactose being incorporated at about the time of aggregation of subunits to protein 17-18s. Most, if not all, the carbohydrate is added to thyroglobulin before it is iodinated.
Collapse
|
30
|
|
31
|
Abstract
1. Cerebral RNA of adult and newborn rats was labelled in vivo by intracervical injection of [5-(3)H]uridine or [(32)P]phosphate. Hepatic RNA of similar animals was labelled by intraperitoneal administration of [6-(14)C]orotic acid. Nuclear and cytoplasmic fractions were isolated and purified by procedures involving extraction with phenol and repeated precipitation with ethanol. 2. The fraction of pulse-labelled RNA from cerebral nuclei that hybridized to homologous DNA exhibited a wide range of turnover values and was heterogeneous in sucrose density gradients. 3. Base composition of the hybridizable RNA was similar to that of the total pulse-labelled material; both were DNA-like. 4. Pulse-labelled cerebral nuclear RNA hybridized to a greater extent than cytoplasmic RNA for at least a week after administration of labelled precursor. This finding suggested that cerebral nuclei contained a hybridizable component that was not transferred to cytoplasm. 5. The rates of decay of the hybridizable fractions of cerebral nuclei and cytoplasm were faster in the newborn animal than in the adult. Presumably a larger proportion of labile messenger RNA molecules was present in the immature brain. 6. Cerebral nuclear and cytoplasmic RNA fractions from newborn or adult rats, labelled either in vivo for periods varying from 4min. to 7 days or in vitro by exposure to [(3)H]-dimethyl sulphate, uniformly hybridized more effectively than the corresponding hepatic preparation. These data suggested that a larger proportion of RNA synthesis was oriented towards messenger RNA formation in brain than in liver.
Collapse
|
32
|
Iványi J, Maler M, Wudl L, Sercarz E. High-dose delay of the immune response. Effect of actinomycin D on continuation of the immune response in vitro. J Exp Med 1968; 127:1149-63. [PMID: 4172460 PMCID: PMC2138495 DOI: 10.1084/jem.127.6.1149] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The continuation of the primary and secondary antibody response to human serum albumin (HSA), induced in vivo, was followed in explanted chicken spleen fragments. The effect of actinomycin D (AMD) on the in vitro response was studied in spleens from chickens injected with various doses of HSA and removed at differing intervals after injection. The antibody response of "early spleen" cultures was AMD-sensitive, while cultures of spleens removed later were AMD-resistant. It was suggested that this shift represented the development of cells with in vivo preformed RNA involved in specific immunoglobulin synthesis. With increasing doses of HSA, the AMD-sensitive phase was prolonged, suggesting the delay of mRNA formation or some other AMD-inhibitable process in vivo. With large doses of HSA, the immune response in vitro was decreased, starting after a 1-2 day delay and not occurring in the presence of AMD. Massive doses of HSA completely inhibited the continuation of the response in vitro by spleen fragments removed between the 2nd and 5th day after injection. The results point to the controlling role of antigen dose in determining the onset of macromolecular synthesis during immunocyte maturation.
Collapse
|
33
|
Cartouzou G, Attali JC, Lissitzky S. [Messenger ribonucleic acids of the thyroid gland. I. Rapidly-labelled RNA of nuclei and polysomes]. EUROPEAN JOURNAL OF BIOCHEMISTRY 1968; 4:41-54. [PMID: 4967137 DOI: 10.1111/j.1432-1033.1968.tb00171.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
34
|
|
35
|
|
36
|
|
37
|
|
38
|
Cavalieri RR, Searle GL. Biosynthesis of thyroglobulin and sub-units in the rat thyroid gland in vivo. Biochem J 1967; 102:25C-27C. [PMID: 6029597 PMCID: PMC1270298 DOI: 10.1042/bj1020025c] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
39
|
|
40
|
Abstract
Template RNA in adrenal glands appears to be heterogeneous in stability. The RNA that regulates synthesis of a large fraction of adrenal protein has a turnover time of 4 hours or less. The remainder of adrenal-protein synthesis, including synthesis of protein that mediates the rapid steroidogenic response to ACTH, depends on RNA with considerably greater stability.
Collapse
|
41
|
Warner JR, Soeiro R, Birnboim HC, Girard M, Darnell JE. Rapidly labeled HeLa cell nuclear RNA. I. Identification by zone sedimentation of a heterogeneous fraction separate from ribosomal precursor RNA. J Mol Biol 1966; 19:349-61. [PMID: 5969070 DOI: 10.1016/s0022-2836(66)80009-8] [Citation(s) in RCA: 301] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
42
|
Tsanev RG, Markov GG, Dessev GN. Incorporation of labelled precursors into the electrophoretic fractions of rat-liver ribonucleic acid. Biochem J 1966; 100:204-10. [PMID: 5966538 PMCID: PMC1265111 DOI: 10.1042/bj1000204] [Citation(s) in RCA: 45] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
1. Incorporation of [(32)P]orthophosphate and of [2-(14)C]orotic acid into rat-liver RNA was studied by agar-gel electrophoresis by using u.v.-densitometry and radioautography of dried agar electrophoretograms. 2. During the electrophoresis some low-molecular-weight contaminants, including inorganic phosphate present in the RNA preparations, were separated from the RNA fractions. Since nucleoside mono-, di- and tri-phosphates still interfered, the RNA preparations had to be subjected to a purification procedure [Sephadex G-25 or Dowex 1 (X8)]. 3. In RNA extracted from cytoplasm, isolated microsomes or ribosomes, whatever variations were made in the phenol procedure no special rapidly labelled RNA fraction was detected other than ;soluble' RNA and the ribosomal RNA components. 4. When the whole homogenate or cytoplasmic fraction was treated only with phenol (pH6) a considerable part of the cytoplasmic RNA was not extracted. The treatment of the cytoplasmic fraction with sodium dodecyl sulphate before the addition of phenol increased the yield of the high-molecular-weight RNA and at the same time a higher specific activity was found for the faster ribosomal RNA component. 5. The presence of four distinct rapidly labelled RNA fractions was established in the RNA not extracted by phenol, and they moved slower than the ribosomal RNA. They were extracted only with the use of phenol-sodium dodecyl sulphate at an elevated temperature.
Collapse
|
43
|
|
44
|
Stavitsky AB, Gusdon JP. Symposium on in vitro studies of the immune response. IV. Role of nucleic acids in the anamnestic antibody response. BACTERIOLOGICAL REVIEWS 1966; 30:418-26. [PMID: 5327759 PMCID: PMC441003 DOI: 10.1128/br.30.2.418-426.1966] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
45
|
Tata JR. Hormones and the synthesis and utilization of ribonucleic acids. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1966; 5:191-250. [PMID: 5337696 DOI: 10.1016/s0079-6603(08)60235-4] [Citation(s) in RCA: 175] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
46
|
Abstract
Noniodinated subunits of thyroglobulin can aggregate, but iodination of the aggregate is required for its stabilization (maturation). Rat-thyroid slices incorporate amino acids into subunits, but cannot form mature thyroglobulin from the newly synthesized subunits. This defect leads to an accumulation of 16S and 12S proteins, although the preexisting thyroglobulin is 19S. Accumulation of 16S and 12S proteins can be produced in rat thyroids by the administration to the animals of a thiocarbamide derivative, methimazole. Upon withdrawal of methimazole, iodination of the 16S and 12S proteins proceeds, and 19S protein appears.
Collapse
|
47
|
|
48
|
|
49
|
|
50
|
|