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High mobility group proteins of amphibian oocytes: a large storage pool of a soluble high mobility group-1-like protein and involvement in transcriptional events.
Abstract
Oocytes of several amphibian species (Xenopus laevis, Rana temporaria, and Pleurodeles waltlii) contained a relatively large pool of nonchromatin-bound, soluble high mobility group (HMG) protein with properties similar to those of calf thymus proteins HMG-1 and HMG-2 (protein HMG-A; A, amphibian). About half of this soluble HMG-A was located in the nuclear sap, the other half was recovered in enucleated ooplasms. This protein was identified by its mobility on one- and two-dimensional gel electrophoresis, by binding of antibodies to calf thymusHMG-1 to polypeptides electrophoretically separated and blotted on nitrocellulose paper, and by tryptic peptide mapping of radioiodinated polypeptides. Most, if not all, of the HMG-A in the soluble nuclear protein fraction, preparatively defined as supernatant obtained after centrifugation at 100,000 g for 1 h, was in free monomeric form, apparently not bound to other proteins. On gel filtration it eluted with a mean peak corresponding to an apparent molecular weight of approximately 25,000; on sucrose gradient centrifugation it appeared with a very low S value (2-3 S), and on isoelectric focusing it appeared in fractions ranging from pH approximately 7 to 9. This soluble HMG-A was retained on DEAE-Sephacel but could be eluted already at moderate salt concentrations (0.2 M KCl). In oocytes of various stages of oogenesis HMG-A was accumulated in the nucleus up to concentrations of approximately 14 ng per nucleus (in Xenopus), corresponding to approximately 0.2 mg/ml, similar to those of the nucleosomal core histones. This nuclear concentration is also demonstrated using immunofluorescence microscopy. When antibodies to bovine HMG-1 were microinjected into nuclei of living oocytes of Pleurodeles the lateral loops of the lampbrush chromosomes gradually retracted and the whole chromosomes condensed. As shown using electron microscopy of spread chromatin from such injected oocyte nuclei, this process of loop retraction was accompanied by the appearance of variously-sized and irregularly-spaced gaps within transcriptional units of chromosomal loops but not of nucleoli, indicating that the transcription of non-nucleolar genes was specifically inhibited by this treatment and hence involved an HMG-1-like protein. These data show that proteins of the HMG-1 and -2 category, which are usually chromatin-bound components, can exist, at least in amphibian oocytes, in a free soluble monomeric form, apparently not bound to other molecules. The possible role of this large oocyte pool of soluble HMG-A in early embryogenesis is discussed as well as the possible existence of soluble HMG proteins in other cells.
Adamson,
Histone synthesis in early amphibian development: histone and DNA syntheses are not co-ordinated.
1974, Pubmed,
Xenbase
Adamson,
Histone synthesis in early amphibian development: histone and DNA syntheses are not co-ordinated.
1974,
Pubmed
,
Xenbase
Bhullar,
The large high mobility group proteins of rainbow trout are localized predominantly in the nucleus and nucleoli of a cultured trout cell line.
1981,
Pubmed
Bidney,
Purification from cultured hepatoma cells of two nonhistone chromatin proteins with preferential affinity for single-stranded DNA: apparent analogy with calf thymus HMG proteins.
1978,
Pubmed
Bona,
Antibodies of RNA polymerase II (B) inhibit transcription in Lampbrush chromosomes after microinjection into living amphibian oocytes.
1981,
Pubmed
,
Xenbase
Bruder,
Characteristics of membrane-bound and soluble forms of xanthine oxidase from milk and endothelial cells of capillaries.
1982,
Pubmed
Bustin,
Antigenic determinants of high mobility group chromosomal proteins 1 and 2.
1982,
Pubmed
Bustin,
Immunological relatedness of high mobility group chromosomal proteins from calf thymus.
1978,
Pubmed
Bustin,
Antibodies against chromosomal HMG proteins stain the cytoplasm of mammalian cells.
1979,
Pubmed
Dabauvalle,
Karyophilic proteins: polypeptides synthesized in vitro accumulate in the nucleus on microinjection into the cytoplasm of amphibian oocytes.
1982,
Pubmed
,
Xenbase
Dumont,
Oogenesis in Xenopus laevis (Daudin). I. Stages of oocyte development in laboratory maintained animals.
1972,
Pubmed
,
Xenbase
Elder,
Radioiodination of proteins in single polyacrylamide gel slices. Tryptic peptide analysis of all the major members of complex multicomponent systems using microgram quantities of total protein.
1977,
Pubmed
Gabrielli,
Characterisation of a chromatin fraction bearing pulse-labelled RNA. 2. Quantification of histones and high-mobility-group proteins.
1981,
Pubmed
Georgieva,
Distribution of high mobility group and other acid-soluble proteins in fractionated chromatin.
1981,
Pubmed
Gigi,
Detection of a cytokeratin determinant common to diverse epithelial cells by a broadly cross-reacting monoclonal antibody.
1982,
Pubmed
Goodwin,
The presence of high mobility group non-histone chromatin proteins in isolated nucleosomes.
1977,
Pubmed
Goodwin,
Are the high mobility group non-histone chromosomal proteins associated with 'active' chromatin?
1978,
Pubmed
Gordon,
Heterogeneous binding of high mobility group chromosomal proteins to nuclei.
1981,
Pubmed
Isackson,
High mobility group chromosomal proteins isolated from muclei and cytosol of cultured hepatoma cells are similar.
1980,
Pubmed
Isackson,
Preferential affinity of high molecular weight high mobility group non-histone chromatin proteins for single-stranded DNA.
1979,
Pubmed
Jackson,
Chromatin fractionation procedure that yields nucleosomes containing near-stoichiometric amounts of high mobility group nonhistone chromosomal proteins.
1979,
Pubmed
Javaherian,
Nonhistone proteins HMG1 and HMG2 change the DNA helical structure.
1978,
Pubmed
Kleinschmidt,
Soluble acidic complexes containing histones H3 and H4 in nuclei of Xenopus laevis oocytes.
1982,
Pubmed
,
Xenbase
Krohne,
Immunological identification and localization of the predominant nuclear protein of the amphibian oocyte nucleus.
1980,
Pubmed
,
Xenbase
Krohne,
A major soluble acidic protein located in nuclei of diverse vertebrate species.
1980,
Pubmed
,
Xenbase
Krohne,
Immunological localization of a major karyoskeletal protein in nucleoli of oocytes and somatic cells of Xenopus laevis.
1982,
Pubmed
,
Xenbase
Kuehl,
Distribution of high mobility group proteins among domains of trout testis chromatin differing in their susceptibility to micrococcal nuclease.
1980,
Pubmed
Laskey,
Assembly of SV40 chromatin in a cell-free system from Xenopus eggs.
1977,
Pubmed
,
Xenbase
Levy,
A study of the localization of high mobility group proteins in chromatin.
1978,
Pubmed
Mathew,
Studies on the association of the high mobility group non-histone chromatin proteins with isolated nucleosomes.
1979,
Pubmed
Mathis,
Structure of transcribing chromatin.
1980,
Pubmed
Merriam,
The germinal vesicle nucleus of Xenopus laevis oocytes as a selective storage receptacle for proteins.
1976,
Pubmed
,
Xenbase
Rechsteiner,
Microinjection of the nonhistone chromosomal protein HMG1 into bovine fibroblasts and HeLa cells.
1979,
Pubmed
Romani,
Solid phase radioimmunoassay for chromosomal components.
1980,
Pubmed
Salik,
Electrophoretic analysis of the stored histone pool in unfertilized sea urchin eggs: quantification and identification by antibody binding.
1981,
Pubmed
Scalenghe,
Large scale isolation of nuclei and nucleoli from vitellogenic oocytes of Xenopus laevis.
1978,
Pubmed
,
Xenbase
Scheer,
Injected histone antibodies interfere with transcription of lampbrush chromosome loops in oocytes of Pleurodeles.
1979,
Pubmed
Scheer,
Classification of loops of lampbrush chromosomes according to the arrangement of transcriptional complexes.
1976,
Pubmed
Scheer,
Lengths and patterns of transcriptional units in the amplified nucleoli of oocytes of Xenopus laevis.
1977,
Pubmed
,
Xenbase
Smith,
Immunochemical studies of high mobility group non-histone chromatin proteins HMG 1 and HMG 2.
1978,
Pubmed
Switzer,
A highly sensitive silver stain for detecting proteins and peptides in polyacrylamide gels.
1979,
Pubmed
Towbin,
Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications.
1979,
Pubmed
Vidali,
Selective release of chromosomal proteins during limited DNAase 1 digestion of avian erythrocyte chromatin.
1977,
Pubmed
Walker,
The primary structures of non-histone chromosomal proteins HMG 1 and 2.
1980,
Pubmed
Walker,
The similarity between the primary structures of two non-histone chromosomal proteins.
1976,
Pubmed
Walker,
The primary structure of a non-histone chromosomal protein.
1977,
Pubmed
Walker,
The primary structure of the nucleosome-associated chromosomal protein HMG 14.
1979,
Pubmed
Weintraub,
Chromosomal subunits in active genes have an altered conformation.
1976,
Pubmed
Weisbrod,
Interaction of HMG 14 and 17 with actively transcribed genes.
1980,
Pubmed
Weisbrod,
Active chromatin of oocytes injected with somatic cell nuclei or cloned DNA.
1982,
Pubmed
,
Xenbase
Woodland,
The synthesis and storage of histones during the oogenesis of Xenopus laevis.
1977,
Pubmed
,
Xenbase
Wu,
Comparative studies on microinjected high-mobility-group chromosomal proteins, HMG1 and HMG2.
1981,
Pubmed