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M Goulding

Publications and source records attributed to M Goulding.

26 records · Page 2Linked to original sources
PubMed1992

The ubiquitous transactivator Zfp-38 is upregulated during spermatogenesis with differential transcription.

We describe the complete nucleotide sequence of a full length cDNA clone encoding a new mouse zinc finger protein gene, Zfp-38 and localize it on chromosome 5 by the interspecific backcross analysis. The N-terminal domain of the Zfp-38 protein (64 kDa) contains 358 amino acids and the C-terminal domain of 197 residues encodes 7 zinc fingers. We also present evidence that Zfp-38 is a strong transcriptional activator. The transactivation domain was localized in the non finger region and a fusion protein containing 112 amino acid residues from this region of the Zfp-38 and the DNA binding domain of the yeast Gal 4 protein, very efficiently transactivated the expression of a reporter CAT plasmid, harboring the Gal4 target site. By in situ hybridization and northern blotting technique, the Zfp-38 transcript can be detected at a highly elevated level during spermatogenesis. Its expression accompanies the progression from pachytene spermatocytes to round spermatids. The undifferentiated spermatogonia or the haploid elongated spermatid and the spermatozoa do not show any detectable level of the transcript. Interestingly, other tissues express low levels of a slightly shorter transcript with a different 5' end as determined by RNase protection. The presence of both a transcriptional activating domain and 7 DNA binding zinc fingers, coupled with the cell type(s) specific expression pattern, suggests that Zfp-38 has the potential to regulate transcription during spermatogenesis.

Amino Acid Sequence↗
PubMed1991

The molecular basis of the undulated/Pax-1 mutation.

The murine paired box gene Pax-1 has been associated with the mouse developmental mutant undulated (un), which exhibits malformations in the vertebral column. In un mice, a point mutation leading to a Gly-Ser exchange in a conserved part of the paired domain of Pax-1 is present. Here we show that Pax-1 encodes a DNA-binding protein with transcriptional activating properties. The DNA-binding specificity of the Pax-1 protein has been extensively analyzed in gel shift assays, and in conjunction with binding interference experiments, a DNA-binding core motif was defined. Comparison of the DNA-binding properties of wild-type and un Pax-1 proteins demonstrates that the Gly-Ser replacement at position 15 within the paired domain dramatically decreases the DNA-binding affinity of the un Pax-1 protein and alters its DNA-binding specificity. These results decipher the molecular basis of the un mutation.

Alkylation↗
PubMed1990

Induction of c-fos mRNA and protein in neurons and glia after traumatic brain injury: pharmacological characterization.

Focal brain injury in mice induced c-fos mRNA and protein in neurons throughout the damaged neocortex, including the piriform and the entorhinal cortices, as well as in nonneural brain cells (e.g., glia, pia, ependyma). The pattern of c-fos induction after injury suggested that injury led to spreading depression which then led to c-fos induction in neurons. Human neurons in the temporal cortex and hippocampus also showed c-fos protein induction after neurosurgical trauma. The c-fos mRNA and protein induction in mouse neurons was prevented by the noncompetitive NMDA antagonist ketamine but only partially inhibited by the voltage-dependent calcium channel antagonist nifedipine and the calmodulin antagonist trifluoperazine. The c-fos protein induction in nonneural brain cells after injury was not affected by these drugs. Thus, induction of c-fos in neocortical neurons after focal brain injury is partly NMDA receptor mediated.

Animals↗
PubMed1990

Structure and expression of the mouse Oct2a and Oct2b, two differentially spliced products of the same gene.

A large family of tissue-specific nuclear proteins interact with the octamer motif ATTTGCAT, a transcriptional regulatory element found in the promoter and enhancer sequences of many genes. As a step towards elucidating the mechanism of this regulation, cDNA clones of the mouse Oct2 protein were isolated. One, called here Oct2b, encodes a larger variant of the previously described Oct2a proteins. The Oct2b cDNA has an insertion of 74 bp close to the 3' end which creates an open reading frame distinct from Oct2a. As a result, the Oct2b protein has a carboxy end which is similar to that of the ubiquitous octamer-binding protein Oct1. Analysis of the Oct2 gene shows that Oct2a and Oct2b are differentially spliced products of the same gene. The insertion in the Oct2b cDNA results from the inclusion of an additional exon in the mRNA which would otherwise reside in an intron sequence of the Oct2a transcript. RNA analysis demonstrates that both Oct2a and 2b mRNAs are most abundant in B-cells but they are also expressed in a variety of tissues including brain, intestine, testis, kidney, as well as in embryos. Interestingly, the ratio of Oct2a and 2b varies among tissues. In situ hybridization studies during mouse embryogenesis show that the Oct2 gene is widely expressed in the developing nervous system. In contrast, expression in the adult brain is confined to very specific areas which include the suprachiasmatic and medial mammillary nuclei, hippocampus, olfactory tract and the olfactory bulb. Oct2 proteins are present in both neuronal and oligodendroglial cells, although they are more abundant in glial cells.

Amino Acid Sequence↗
PubMed1989

Long-term potentiation and the induction of c-fos mRNA and proteins in the dentate gyrus of unanesthetized rats.

We tested the hypothesis that the nuclear proto-oncogene c-fos is involved in long-term potentiation (LTP) of the perforant path-dentate gyrus synapse in awake freely moving rats. High-frequency stimulation that produced LTP induced c-fos mRNA and protein in the dentate granule cells but not in CA1, CA3, or the entorhinal cortex. However, the degree of LTP induction did not correlate with the degree of c-fos induction. Agents that interfered with the production of LTP (e.g. NMDA antagonists) also prevented c-fos induction. Low-frequency stimulation did not lead to either LTP or c-fos induction. However, c-fos induction did not necessarily follow LTP production because some high-frequency stimulation protocols that produced good LTP did not lead to c-fos induction. Thus, c-fos induction is clearly not related to LTP production in unanaesthetized rats, but it remains to be determined if it plays some role in LTP maintenance.

Adaptation, Physiological↗
PubMed1985

Cyclic AMP, nuclear protein kinase and the PY815 cell cycle.

A substantial increase in cyclic AMP-dependent protein kinase activity occurred in nuclei of PY815 mastocytoma cells during G1 phase growth arrest by DB cyclic AMP and the increased nuclear protein kinase was accompanied by changes in nuclear protein phosphorylation. However, there was no obligatory association between the rise in nuclear cyclic AMP-dependent protein kinase in G1 phase and growth arrest because nuclear cyclic AMP-dependent protein kinase also increased during G1 phase in cycling PY815 cells synchronized with amethopterin. These observations suggest that maintenance of high cyclic AMP levels during G1 phase may cause growth arrest by activating a cyclic AMP-dependent protein kinase that normally increases in PY815 cell nuclei during G1 phase.

Animals↗