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G H Goodwin

Publications and source records attributed to G H Goodwin.

At least 73 records · Page 4Linked to original sources
PubMed1979

Studies on the association of the high mobility group non-histone chromatin proteins with isolated nucleosomes.

Nucleosomes have been isolated from rabbit thymus by sucrose gradient centrifugation, and their high mobility group (HMG) protein content analysed by electrophoresis on polyacrylamide gels. The results suggest that proteins HMG 14 and HMG 17 are associated with the core particle of the nucleosome, and that there are two or more sub-populations of both HMG 1 and HMG 2 molecules. One sub-population appears to be fairly tightly bound to the nucleosome, while another is rapidly released from the chromatin by digestion with micrococcal nuclease. The latter fraction may participate in a higher order folding of the nucleosomes.

Animals↗
PubMed1978

Studies on the tissue specificity of the high-mobility-group non-histone chromosomal proteins from calf.

The high-mobility-group (HMG) non-histone chromosomal proteins from calf thymus, liver, spleen and kidney were extracted, and fractionated by CM-Sephadex chromatography and trichloroacetic acid precipitation. The isolated proteins HMG 1, HMG 2 and HMG 17 from the tissues were compared by polyacrylamide-gel electrophoresis, isoelectric focusing and amino acid analysis. The results show that the three proteins are very similar in the tissues studied, implying a lack of tissue specificity.

Amino Acids↗
PubMed1978

Studies on the degradation of high mobility group non-histone chromosomal proteins.

During the isolation of high mobility group non-histone proteins from calf thymus chromatin by methods described previously (e.g. Goodwin, G.H., Nicolas, R.H. and Johns, E.W. (1975) Biochim. Biophys, Acta. 405, 280--291) protein degradation occurs resulting in a number of proteins appearing in the chromatin extracts which are not present in high mobility group protein preparations in which proteolysis has been completely inhibited. These extra proteins, formerly numbered high mobility group proteins 3, 5, 6 and 8, are thus probably degradation products of other nuclear proteins, produced during the isolation procedure. From the amino acid analyses, tryptic peptides and N-terminal sequences, it is concluded that high mobility group protein 3 is probably a degradation product of high mobility group protein 1. The amino acid analysis of high mobility group protein 8 is very similar to that of the N-terminal half of histone H1 suggesting that high mobility group protein 8 is a degradation product of this histone.

Amino Acids↗
PubMed1978

Are the high mobility group non-histone chromosomal proteins associated with 'active' chromatin?

When 10--20% of the DNA in thymus and liver nuclei is rendered acid-soluble by DNAase I digestion, under conditions which may be expected to specifically degrade away most of the transcribed sequences, very little of the high-mobility-group non-histone proteins are released from the nuclei. Therefore, high-mobility-group proteins are probably not specifically associated with this portion of the genome.

Animals↗
PubMed1978

Studies on the conformational properties of the high-mobility-group chromosomal protein HMG 17 and its interaction with DNA.

The conformation of the non-histone chromatin protein, HMG 17, has been studied using circular dichroism, infrared and nuclear magnetic resonance spectroscopies, and by small-angle scattering. The results show that in free solution this protein has little or no secondary or tertiary structure in contrast to the other high-mobility-group proteins, HMG 1 and 2, which exhibit highly ordered structures. Protein HMG 17 binds to calf thymus DNA in an ionic-dependent manner, precipitating the DNA at high protein/DNA ratio. The nuclear magnetic resonance data suggest that the principle DNA-binding segment of HMG 17 is that between about residues 15 and 40.

Animals↗
PubMed1977

A comparison of the amino-terminal sequences of two calf-thymus chromatin non-histone proteins.

The N-terminal sequences of two calf-thymus non-histone chromosomal proteins, HMG-1 and HMG-2, are compared. Both N-terminal sequences are basic, and differ at only one position. This contrasts with the C-terminal portion of HMG-1 which we have previously shown to be high in acidic residues. There is no obvious sequence homology with any of the known sequences of the histones.

Amino Acid Sequence↗
PubMed1977

Interaction of non-histone chromosomal proteins HMG1 and HMG2 with DNA.

Interaction between non-histone protein HMG1 or HMG2 and DNA has been studied by using thermal denaturation and circular dichroism (CD) spectroscopy. We have made the following observations. 1. The binding of each of these two proteins to DNA stabilizes the latter, as shown by an increase in melting temperature of 20 degrees C (from 45 degrees C to about 65 degrees C). 2. There are 6.0 amino acids/nucleotide in HMG1-bound DNA and 5.0 in HMGI-bound DNA which suggests that each HMB1 moleculae would cover about 20 base pairs of DNA and each HMG2 molecule would cover about 25 base pairs. 3. The alpha-helical content of these two non-histone proteins in the complexes, estimated from the CD value at 220 nm, is about one third to one half that of total proteins in calf thymus chromatin. 4. DNA conformation is distorted only slightly by the binding of protein HMG1 or HMG2. 5. Neither the melting nor the CD properties of HMG1-DNA or HMG2-DNA complexes differ substantially whether they are prepared by NaCl-gradient dialysis in urea or by direct mixing of protein and DNA at 0.15 M NaCl, followed by dialysis against the same buffer i.e. 0.25 mM EDTA (pH 8.0).

Chromosomal Proteins, Non-Histone↗