Analysis of putative high-mobility-group (HMG) proteins in neuronal and glial nuclei from rabbit brain

1981 ◽  
Vol 6 (6) ◽  
pp. 673-679 ◽  
Author(s):  
Paul Greenwood ◽  
Julie C. Silver ◽  
Ian R. Brown
Keyword(s):  
High Mobility ◽  
High Mobility Group ◽  
Rabbit Brain ◽  
Hmg Proteins

scholarly journals Phosphorylation of high mobility group 1 protein by phospholipid-sensitive Ca2+-dependent protein kinase from pig testis

1985 ◽  
Vol 227 (1) ◽  
pp. 271-276 ◽  
Author(s):  
K Kimura ◽  
N Katoh ◽  
K Sakurada ◽  
S Kubo
Keyword(s):  
Protein Kinase ◽  
High Mobility ◽  
Particulate Fraction ◽  
High Mobility Group ◽  
Hmg Proteins ◽  
Dependent Protein Kinase ◽  
Histone Proteins ◽  
Km Value ◽  
Dependent Protein ◽  
Group 1

Phospholipid-sensitive Ca2+-dependent protein kinase was partially purified from total particulate fraction of pig testis. The enzyme phosphorylated high mobility group 1 protein (HMG 1), one of the major chromatin-associated non-histone proteins. Other HMG proteins (HMG 2, 14 and 17) were not phosphorylated by the enzyme. Exhaustive phosphorylation of HMG 1 revealed that 1 mol of phosphate was incorporated/mol of HMG 1. The apparent Km value for HMG 1 was 3.66 microM. 1,3-Diolein stimulated the phosphorylation at 10 microM-Ca2+ in the presence of phosphatidylserine. The phosphorylation of HMG 1 was inhibited by adriamycin, an inhibitor of spermatogenesis.

scholarly journals Concentrations of high-mobility-group proteins in the nucleus and cytoplasm of several rat tissues.

1984 ◽  
Vol 99 (2) ◽  
pp. 648-654 ◽  
Author(s):  
L Kuehl ◽  
B Salmond ◽  
L Tran
Keyword(s):  
High Mobility ◽  
High Mobility Group ◽  
Rat Tissues ◽  
Two Dimensional ◽  
Hmg Proteins ◽  
High Mobility Group Proteins

Nuclear and cytoplasmic fractions were isolated from various tissues of the rat by a nonaqueous technique. The high-mobility-group (HMG) proteins were extracted from these fractions with acid and separated by one- and two-dimensional PAGE. The concentrations of high-mobility-group proteins HMG1, HMG2, and HMG17 in the nucleus and cytoplasm were then estimated from the staining intensities of the electrophoretic bands. The cytoplasmic concentrations of these proteins were very low--usually less than 1/30 of those present in the corresponding nuclear fractions. For the tissues studied (liver, kidney, heart, and lung), the concentrations of HMG proteins in the nucleus did not differ significantly from one tissue to another. Averaged over the four tissues investigated, there were 0.28 molecule of HMG1, 0.18 molecule of HMG2, and 0.46 molecule of HMG17 per nucleosome. These values are considerably higher than those that have been reported previously.

scholarly journals 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.

1983 ◽  
Vol 97 (3) ◽  
pp. 838-848 ◽  
Author(s):  
J A Kleinschmidt ◽  
U Scheer ◽  
M C Dabauvalle ◽  
M Bustin ◽  
W W Franke
Keyword(s):  
Rana Temporaria ◽  
Peptide Mapping ◽  
Gradient Centrifugation ◽  
High Mobility ◽  
High Mobility Group ◽  
Monomeric Form ◽  
Hmg Proteins ◽  
Amphibian Species ◽  
Large Oocyte ◽  
Calf Thymus

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 thymus HMG-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.

scholarly journals Changes in quantities of high-mobility-group protein 1 in oviduct cellular fractions after oestrogen stimulation

1981 ◽  
Vol 198 (1) ◽  
pp. 85-90 ◽  
Author(s):  
C T Teng ◽  
C S Teng
Keyword(s):  
Microsomal Fraction ◽  
High Mobility ◽  
Quantitative Change ◽  
High Mobility Group ◽  
Nuclear Fraction ◽  
Hmg Proteins ◽  
High Mobility Group Protein ◽  
Group Protein ◽  
Oviduct Cell

Antiserum against chick oviduct high-mobility-group protein 1 (HMG 1) has been induced in the rabbit. With this antiserum, immunobiochemical techniques have been used to probe the quantitative change of HMG 1 in the cellular fractions of chick oviduct before or after oestrogen stimulation. HMG 1 is detectable in the cytosol, microsomal and nuclear fraction of the chick oviduct cell. After administration of oestrogen to young chicks in vivo for 5 days, the quantity of HMG 1 is increased 4-fold in the cytosol, 3.5-fold in the microsomal fraction and 1.6-fold in the nuclear fraction. The finding of large amounts of HMG 1 in cytoplasm of oviduct cell is not likely due to its leakage from the nucleus. We anticipate that HMG 1 is synthesized in the cytoplasm and then transported into the nucleus. The synthesis and transportation of HMG proteins is probably regulated by oestrogen.

scholarly journals Macronuclei and micronuclei in Tetrahymena thermophila contain high-mobility-group-like chromosomal proteins containing a highly conserved eleven-amino-acid putative DNA-binding sequence.

1991 ◽  
Vol 11 (1) ◽  
pp. 166-174 ◽  
Author(s):  
I G Schulman ◽  
T Wang ◽  
M Wu ◽  
J Bowen ◽  
R G Cook ◽  
...  
Keyword(s):  
Amino Acid ◽  
Dna Binding ◽  
Tetrahymena Thermophila ◽  
High Mobility ◽  
Amino Acid Sequences ◽  
High Mobility Group ◽  
Binding Motif ◽  
Hmg Proteins ◽  
Chromosomal Proteins ◽  
Conserved Sequence

HMG (high-mobility-group protein) B and HMG C are abundant nonhistone chromosomal proteins isolated from Tetrahymena thermophila macronuclei with solubilities, molecular weights, and amino acid compositions like those of vertebrate HMG proteins. Genomic clones encoding each of these proteins have been sequenced. Both are single-copy genes that encode single polyadenylated messages whose amounts are 10 to 15 times greater in growing cells than in starved, nongrowing cells. The derived amino acid sequences of HMG B and HMG C contain a highly conserved sequence, the HMG 1 box, found in vertebrate HMGs 1 and 2, and we speculate that this sequence may represent a novel, previously unrecognized DNA-binding motif in this class of chromosomal proteins. Like HMGs 1 and 2, HMGs B and C contain a high percentage of aromatic amino acids. However, the Tetrahymena HMGs are small, are associated with nucleosome core particles, and can be specifically extracted from macronuclei by elutive intercalation, properties associated with vertebrate HMGs 14 and 17, not HMGs 1 and 2. Thus, it appears that these Tetrahymena proteins have features in common with both of the major subgroups of higher eucaryotic HMG proteins. Surprisingly, a linker histone found exclusively in transcriptionally inactive micronuclei also has several HMG-like characteristics, including the ability to be specifically extracted from nuclei by elutive intercalation and the presence of the HMG 1 box. This finding suggests that at least in T. thermophila, proteins with HMG-like properties are not restricted to regions of transcriptionally active chromatin.

scholarly journals A high-mobility-group protein and its cDNAs from Drosophila melanogaster.

1992 ◽  
Vol 12 (5) ◽  
pp. 1915-1923 ◽  
Author(s):  
C R Wagner ◽  
K Hamana ◽  
S C Elgin
Keyword(s):  
Drosophila Melanogaster ◽  
Amino Acid ◽  
Acid Content ◽  
Amino Acid Content ◽  
High Mobility ◽  
High Mobility Group ◽  
Chromosome 2 ◽  
Hmg Proteins ◽  
High Mobility Group Protein ◽  
Hmg Protein

We have identified, purified, and characterized a high-mobility-group (HMG) protein and its cDNAs from Drosophila melanogaster. This protein, HMG D, shares most of the characteristics of vertebrate HMG proteins; it is extractable from nuclei with 0.35 M NaCl, is soluble in 5% perchloric acid, is relatively small (molecular weight of 12,000), has both a high basic (24%) and high acidic (24%) amino acid content, and is a DNA-binding protein. HMG D exhibits characteristics of both the vertebrate HMG 1 and 2 class and the HMG 14 and 17 class of proteins. Its amino acid sequence is similar (36% amino acid identity) to that of HMG1, while its size and selective extraction with ethidium bromide are similar to properties of the HMG 14 and 17 class of proteins. HMG D is encoded by a single-copy gene that maps to 57F8-11 on the right arm of chromosome 2. Two transcripts are observed during embryogenesis; the protein is relatively stable throughout development. By the biochemical criteria of size, solubility, and amino acid content, HMG D appears to be the major HMG protein of D. melanogaster.

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