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Acosta-Cárdenas J, Jiménez-García LF, Cruz-Gómez SDJ, Mendoza-von der Borch AP, Segura-Valdez MDL. Microscopic Analysis of Nuclear Speckles in a Viviparous Reptile. Int J Mol Sci 2024; 25:5281. [PMID: 38791320 PMCID: PMC11120696 DOI: 10.3390/ijms25105281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 05/10/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024] Open
Abstract
Nuclear speckles are compartments enriched in splicing factors present in the nucleoplasm of eucaryote cells. Speckles have been studied in mammalian culture and tissue cells, as well as in some non-mammalian vertebrate cells and invertebrate oocytes. In mammals, their morphology is linked to the transcriptional and splicing activities of the cell through a recruitment mechanism. In rats, speckle morphology depends on the hormonal cycle. In the present work, we explore whether a similar situation is also present in non-mammalian cells during the reproductive cycle. We studied the speckled pattern in several tissues of a viviparous reptile, the lizard Sceloporus torquatus, during two different stages of reproduction. We used immunofluorescence staining against splicing factors in hepatocytes and oviduct epithelium cells and fluorescence and confocal microscopy, as well as ultrastructural immunolocalization and EDTA contrast in Transmission Electron Microscopy. The distribution of splicing factors in the nucleoplasm of oviductal cells and hepatocytes coincides with the nuclear-speckled pattern described in mammals. Ultrastructurally, those cell types display Interchromatin Granule Clusters and Perichromatin Fibers. In addition, the morphology of speckles varies in oviduct cells at the two stages of the reproductive cycle analyzed, paralleling the phenomenon observed in the rat. The results show that the morphology of speckles in reptile cells depends upon the reproductive stage as it occurs in mammals.
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Affiliation(s)
- Jeniffer Acosta-Cárdenas
- Laboratorio de Nanobiología Celular, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México—UNAM, Mexico City 04510, Mexico; (J.A.-C.); (L.F.J.-G.); (S.d.J.C.-G.); (A.P.M.-v.d.B.)
- Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - Luis Felipe Jiménez-García
- Laboratorio de Nanobiología Celular, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México—UNAM, Mexico City 04510, Mexico; (J.A.-C.); (L.F.J.-G.); (S.d.J.C.-G.); (A.P.M.-v.d.B.)
| | - Sarai de Jesús Cruz-Gómez
- Laboratorio de Nanobiología Celular, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México—UNAM, Mexico City 04510, Mexico; (J.A.-C.); (L.F.J.-G.); (S.d.J.C.-G.); (A.P.M.-v.d.B.)
| | - Ana Paulina Mendoza-von der Borch
- Laboratorio de Nanobiología Celular, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México—UNAM, Mexico City 04510, Mexico; (J.A.-C.); (L.F.J.-G.); (S.d.J.C.-G.); (A.P.M.-v.d.B.)
| | - María de Lourdes Segura-Valdez
- Laboratorio de Nanobiología Celular, Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México—UNAM, Mexico City 04510, Mexico; (J.A.-C.); (L.F.J.-G.); (S.d.J.C.-G.); (A.P.M.-v.d.B.)
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An Alkaloid from a Highly Invasive Seaweed Increases the Voracity and Reproductive Output of a Model Fish Species. Mar Drugs 2022; 20:md20080513. [PMID: 36005516 PMCID: PMC9410225 DOI: 10.3390/md20080513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 08/07/2022] [Accepted: 08/09/2022] [Indexed: 11/17/2022] Open
Abstract
The invasive macroalga Caulerpa cylindracea has spread widely in the Mediterranean Sea, becoming a favorite food item for native fish for reasons yet unknown. By using a combination of behavioral, morphological, and molecular approaches, herein we provide evidence that the bisindole alkaloid caulerpin, a major secondary metabolite of C. cylindracea, significantly increases food intake in the model fish Danio rerio, influencing the regulation of genes involved in the orexigenic pathway. In addition, we found that the compound improves fish reproductive performance by affecting the hypothalamus-pituitary-gonadal axis. The obtained results pave the way for the possible valorization of C. cylindracea as a sustainable source of a functional feed additive of interest to face critical challenges both in aquaculture and in human nutrition.
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Perez MF, Lehner B. Vitellogenins - Yolk Gene Function and Regulation in Caenorhabditis elegans. Front Physiol 2019; 10:1067. [PMID: 31551797 PMCID: PMC6736625 DOI: 10.3389/fphys.2019.01067] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/05/2019] [Indexed: 12/14/2022] Open
Abstract
Vitellogenins are a family of yolk proteins that are by far the most abundant among oviparous animals. In the model nematode Caenorhabditis elegans, the 6 vitellogenins are among the most highly expressed genes in the adult hermaphrodite intestine, which produces copious yolk to provision eggs. In this article we review what is known about the vitellogenin genes and proteins in C. elegans, in comparison with vitellogenins in other taxa. We argue that the primary purpose of abundant vitellogenesis in C. elegans is to support post-embryonic development and fertility, rather than embryogenesis, especially in harsh environments. Increasing vitellogenin provisioning underlies several post-embryonic phenotypic alterations associated with advancing maternal age, demonstrating that vitellogenins can act as an intergenerational signal mediating the influence of parental physiology on progeny. We also review what is known about vitellogenin regulation - how tissue-, sex- and stage-specificity of expression is achieved, how vitellogenins are regulated by major signaling pathways, how vitellogenin expression is affected by extra-intestinal tissues and how environmental experience affects vitellogenesis. Lastly, we speculate whether C. elegans vitellogenins may play other roles in worm physiology.
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Affiliation(s)
- Marcos Francisco Perez
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Ben Lehner
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
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Medina MF, Cosci A, Cisint S, Crespo CA, Ramos I, Iruzubieta Villagra AL, Fernández SN. Histopathological and biological studies of the effect of cadmium on Rhinella arenarum gonads. Tissue Cell 2012; 44:418-26. [DOI: 10.1016/j.tice.2012.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Revised: 08/14/2012] [Accepted: 08/16/2012] [Indexed: 10/27/2022]
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Bebas P, Kotwica J, Joachimiak E, Giebultowicz JM. Yolk protein is expressed in the insect testis and interacts with sperm. BMC DEVELOPMENTAL BIOLOGY 2008; 8:64. [PMID: 18549506 PMCID: PMC2440742 DOI: 10.1186/1471-213x-8-64] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Accepted: 06/13/2008] [Indexed: 12/02/2022]
Abstract
Background Male and female gametes follow diverse developmental pathways dictated by their distinct roles in fertilization. While oocytes of oviparous animals accumulate yolk in the cytoplasm, spermatozoa slough off most of their cytoplasm in the process of individualization. Mammalian spermatozoa released from the testis undergo extensive modifications in the seminal ducts involving a variety of glycoproteins. Ultrastructural studies suggest that glycoproteins are involved in sperm maturation in insects; however, their characterization at the molecular level is lacking. We reported previously that the circadian clock controls sperm release and maturation in several insect species. In the moth, Spodoptera littoralis, the secretion of glycoproteins into the seminal fluid occurs in a daily rhythmic pattern. The purpose of this study was to characterize seminal fluid glycoproteins in this species and elucidate their role in the process of sperm maturation. Results We collected seminal fluid proteins from males before and after daily sperm release. These samples were separated by 2-D gel electrophoresis, and gels were treated with a glycoprotein-detecting probe. We observed a group of abundant glycoproteins in the sample collected after sperm release, which was absent in the sample collected before sperm release. Sequencing of these glycoproteins by mass spectroscopy revealed peptides bearing homology with components of yolk, which is known to accumulate in developing oocytes. This unexpected result was confirmed by Western blotting demonstrating that seminal fluid contains protein immunoreactive to antibody against yolk protein YP2 produced in the follicle cells surrounding developing oocytes. We cloned the fragment of yp2 cDNA from S. littoralis and determined that it is expressed in both ovaries and testes. yp2 mRNA and YP2 protein were detected in the somatic cyst cells enveloping sperm inside the testis. During the period of sperm release, YP2 protein appears in the seminal fluid and forms an external coat on spermatozoa. Conclusion One of the yolk protein precursors YP2, which in females accumulate in the oocytes to provision developing embryos, appears to have a second male-specific role. It is produced in the testes and released into the seminal fluid where it interacts with sperm. These data reveal unexpected common factor in the maturation of insect eggs and sperm.
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Affiliation(s)
- Piotr Bebas
- Department of Animal Physiology, Faculty of Biology, University of Warsaw, Warsaw, Poland.
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Mori T, Matsumoto H, Yokota H. Androgen-induced vitellogenin gene expression in primary cultures of rainbow trout hepatocytes. J Steroid Biochem Mol Biol 1998; 67:133-41. [PMID: 9877213 DOI: 10.1016/s0960-0760(98)00099-5] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The hormone induction of vitellogenin (Vg) gene expression was investigated in primary cultures of immature male rainbow trout hepatocytes. Vg cDNA was cloned from the liver of a female rainbow trout injected with estradiol-17beta (E2). A Vg mRNA of about 6.6 kb was detected in the hepatocytes after stimulation with 2 x 10(-9) M E2 for 24 h. The intensity of this signal increased with E2 concentration. Several other hormones including progesterone and androgens (testosterone, androsterone, methyltestosterone) also induced Vg mRNA not only at high (2 x 10(-5) M) but also at low (2 x 10(-9) M), physiologically relevant steroid concentrations. Only cortisol failed to do so at any tested concentration but, surprisingly, like progesterone, it induced an additive effect in the presence of E2. On the other hand, tamoxifen drastically reduced the expression of Vg gene whether stimulated by E2 or any other tested steroid. In conclusion, our studies have highlighted the unusual specificity of Vg mRNA induction in fish.
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Affiliation(s)
- T Mori
- Laboratory of Physiology, Faculty of Fisheries, Hokkaido University, Hakodate, Japan.
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Takemori H, Halder SK, Nonaka Y, Fujii T, Ohta M, Hatano O, Okamoto M. Polyadenylation-mediated translational regulation of maternal P450(11beta) mRNA in frog oocytes. EUROPEAN JOURNAL OF BIOCHEMISTRY 1997; 250:197-204. [PMID: 9432009 DOI: 10.1111/j.1432-1033.1997.00197.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Northern blot analysis of bullfrog tissues using a cDNA probe of cytochrome P450(11beta) showed that a large amount of message was present in the ovary as well as in the adrenal tissue. Two kinds of mRNA of different sizes were found in the ovary. Sequence determination of the two cDNAs and analysis by reverse-transcription polymerase chain reaction indicated that the protein encoded by the larger mRNA was identical to the adrenal enzyme, while the protein encoded by the smaller had a truncated sequence lacking an extension peptide necessary for the protein transport to the mitochondria. The mRNAs were present in the oocytes but not in the follicular cells, and their content in an oocyte varied little during its maturation. Immunoblot analyses of the mitochondrial fraction of oocytes failed to demonstrate the presence of P450(11beta) protein. In contrast the eggs were found to contain a large amount of enzymatically active protein. Interestingly the mRNA has a cis-element called cytoplasmic polyadenylation element at its 3' untranslated region. When poly(A) tails of the message prepared from eggs and oocytes were examined by RNase H digestion or reverse-transcription polymerase chain reaction, those of eggs were about 150 nucleotides longer than those of oocytes. These results suggest that translation of the message is stimulated during the oocyte maturation as a result of enhanced polyadenylation at its 3'-end. Finally a finding is presented that progesterone was converted to 11beta-hydroxyprogesterone by the frog P450(11beta), implying that the enzyme expressed in eggs may control a level of progesterone which is needed to initiate the oocyte maturation.
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Affiliation(s)
- H Takemori
- Department of Molecular Physiological Chemistry, Osaka University Medical School, Suita, Japan
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Maitre JL, Valotaire Y, Guguen-Guillouzo C. Estradiol-17β stimulation of vitellogenin synthesis in primary culture of male rainbow trout hepatocytes. ACTA ACUST UNITED AC 1986. [DOI: 10.1007/bf02623408] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Folger K, Anderson JN, Hayward MA, Shapiro DJ. Nuclease sensitivity and DNA methylation in estrogen regulation of Xenopus laevis vitellogenin gene expression. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(18)32143-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Brock ML, Shapiro DJ. Estrogen regulates the absolute rate of transcription of the Xenopus laevis vitellogenin genes. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(20)81911-5] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Shirk PD, Minoo P, Postlethwait JH. 20-Hydroxyecdysone stimulates the accumulation of translatable yolk polypeptide gene transcript in adult male Drosophila melanogaster. Proc Natl Acad Sci U S A 1983; 80:186-90. [PMID: 6401862 PMCID: PMC393336 DOI: 10.1073/pnas.80.1.186] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Yolk polypeptide (YP) synthesis is hormonally stimulated during maturation of adult female Drosophila melanogaster. Synthesis of the three YPs is sex specific and occurs in fat body cells and follicle cells of adult females. However, males have been shown to produce YPs when treated with the steroid hormone 20-hydroxyecdysone (20-HE). By using a cell-free translation system as an assay for YP mRNA, we found that 20-HE also causes the accumulation of translatable YP message in males. In addition, hybridization of cloned copies of genes for both YP1 and YP3 to total RNA from males showed that 20-HE caused the appearance of YP gene transcripts in males. Eight hours after treatment of males with 20-HE, YP gene transcript levels had increased at least 25-fold to approximately 2.7 x 10(6) copies of YP1 gene transcript per adult male fly. In normal adult females, there were 42 x 10(6) copies per fly by 24 hr. There was neither detectable YP synthesis nor translatable YP gene transcript in either normal 1- to 3-day-old males or 24-hr-old males treated with a juvenile hormone analogue. This evidence shows that 20-HE acts to regulate the levels of translatable YP mRNA in male Drosophila.
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Ikeda T, Liu QF, Danielpour D, Officer JB, Iio M, Leland FE, Sirbasku DA. Identification of estrogen-inducible growth factors (estromedins) for rat and human mammary tumor cells in culture. IN VITRO 1982; 18:961-79. [PMID: 7166331 DOI: 10.1007/bf02796371] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The role of polypeptide growth factors (estromedins) as mediators of estrogen-responsive mammary tumor growth is studied in this report. Three possible new mechanisms were investigated that include endocrine, autocrine, and paracrine related growth factors. The first hypothesis being tested is whether estrogens interact with target tissues and cause the biosynthesis and secretion of polypeptide growth factors, which then act as mitogens for normal and neoplastic mammary tissues. Data presented suggest that this mechanism involves estrogen interaction with uterus, kidney, and pituitary gland causing production of growth factors, which then enter the general circulation and promote growth of distant target tissues. This is an endocrine type mechanism. Another type of estromedin control (autocrine control) may be exerted in an autostimulatory way in which the target tissue produces the polypeptide factors for its own growth in response to estrogen stimulation. A variation of the autocrine mechanism may be a paracrine mechanism in which some cells of an estrogen-responsive normal or neoplastic tissue produce growth factors that act on adjacent or neighboring cells. From the data available, all three possible types of growth factors could be functioning synergistically to yield the final result of continuous estrogen responsive tumor growth in vivo.
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Philipp BW, Morgan EA, Shapiro DJ. Quantitation of estrogen effect on Xenopus laevis albumin mRNA levels by hybridization to cloned albumin cDNA. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(18)34359-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Shapiro D. Steroid hormone regulation of vitellogenin gene expression. CRC CRITICAL REVIEWS IN BIOCHEMISTRY 1982; 12:187-203. [PMID: 6123408 DOI: 10.3109/10409238209108706] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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KAWAHARA AKIRA, SATO KAZUKI, AMANO MINORU. Quantitative Analysis of Protein Synthesis Altered by Estrogen in Cultured Xenopus Liver Parenchymal Cell. Dev Growth Differ 1981. [DOI: 10.1111/j.1440-169x.1981.00599.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Vitellogenin is synthesized under estrogen control in the liver, extensively modified, transported to the ovary, and there processed to the yolk proteins lipovitellin and phosvitin. In the frog Xenopus laevis there are at least four distinct but related vitellogenin genes. The two genes A1 and A2 have a 95 percent sequence homology in their messenger RNA coding regions, and contain 33 introns that interrupt the coding region (exons) at homologous positions. Sequences and lengths of analogous introns differ, and many introns contain repetitive DNA elements. The introns in these two genes that have apparently arisen by duplication have diverged extensively by events that include deletions, insertions, and probably duplications. Rapid evolutionary change involving rearrangements and the presence of repeated DNA suggests that the bulk of the sequences within introns may not have any specific function.
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Estrogen regulation of hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase and acetyl-CoA carboxylase in xenopus laevis. J Biol Chem 1981. [DOI: 10.1016/s0021-9258(19)69702-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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18
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Induction of estrogen receptor and reversal of the nuclear/cytoplasmic receptor ratio during vitellogenin synthesis and withdrawal in Xenopus laevis. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)70292-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Abstract
Estradiol-17 beta stimulates the synthesis of numerous proteins exported into the culture medium by Xenopus tadpole liver tissue obtained after stage 50 and throughout metamorphosis to stage 66. Although estrogen-induced vitellogenin can be detected as early as stage 54, it is a minor percentage of the exported proteins until after the completion of metamorphosis. In hepatic tissue obtained after metamorphosis, the hormone evokes the synthesis of vitellogenin specifically without affecting the labeling of other secreted proteins.
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Swiderski RE, Johnson SA, Larkins BA, Graham DE. Sequential Sepharose chromatographic isolation of polysomes and polysomal RNAs depleted in nuclear RNA from Xenopus. Nucleic Acids Res 1979; 6:3685-701. [PMID: 493118 PMCID: PMC327966 DOI: 10.1093/nar/6.11.3685] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Analyses of sequence complexities, stage specific gene expression, and mRNA sequence divergence require polysomal RNA preparations relatively free of nuclear RNA contamination. Conventional procedures for the isolation of uncontaminated polysomal RNAs which rely on sucrose density centrifugations are laborious and unsuitable for large scale isolations. We describe here a method using sequential Sepharose chromatography for isolating polysomes and polysomal RNAs depleted for nuclear RNA. Polysomes and polysomal RNAs isolated from livers of Xenopus stimulated to produce vitellogenin were capable of directing protein synthesis in vitro and showed little evidence of degradation. The polysomal RNAs contained less than 0.5% of nuclear RNA.
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Tata JR, Smith DF. Vitellogenesis: a versatile model for hormonal regulation of gene expression. RECENT PROGRESS IN HORMONE RESEARCH 1979; 35:47-95. [PMID: 390655 DOI: 10.1016/b978-0-12-571135-7.50006-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Abstract
Oestradiol induces vitellogenin synthesis in vitro in liver taken from Xenopus laevis tadpoles that are in late metamorphosis. Inducibility first appears at the end of prometamorphosis, and the response to oestradiol increases during the completion of metamorphosis. Oestradiol continuously present during development does not influence the stage at which tadpole liver becomes inducible. It seems that the acquisition of inducibility is part of the normal development of the liver, and independent of both the supply of oestrogen and the sex of the tadpole.
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Baker H, Shapiro D. Rapid accumulation of vitellogenin messenger RNA during secondary estrogen stimulation of Xenopus laevis. J Biol Chem 1978. [DOI: 10.1016/s0021-9258(17)30418-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Nickol J, Lee K, Kenney F. Changes in hepatic levels of tyrosine aminotransferase messenger RNA during induction by hydrocortisone. J Biol Chem 1978. [DOI: 10.1016/s0021-9258(17)34791-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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