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M Mace

Publications and source records attributed to M Mace.

13 recordsLinked to original sources
PubMed1984

Protein cross-migration during isolation of nuclei from mixtures of heated and unheated HeLa cells.

To investigate the cross-migration of proteins during nuclear isolation heated and control cells were mixed prior to nuclear isolation. These nuclei were stained with fluorescein isothiocyanate (FITC, a protein-specific stain) and with propidium iodide (PI, a DNA-specific stain). Flow cytometric (FCM) analysis showed two populations distinguishable on the basis of protein content. The protein content of the nuclei in the upper population was identical to that for nuclei isolated from heated cells while that for the lower population had a protein content identical to the protein content of nuclei from control cells. This result shows that the heat-induced increase in nuclear protein content occurred throughout the entire population of nuclei (i.e., in G1, S, and G2 nuclei) and that the measured protein content of nuclei was not affected by the presence of the other population during isolation. The capability of the FCM to sort subpopulations from different regions of a histogram was used to separate the subpopulations after analysis. When control cells were prelabeled with [3H]leucine and mixed with unlabeled heated cells, 11% of the radioactivity was found to be associated with the nuclei from heated cells. Autoradiographs showed grains over approximately 99% of the nuclei from heated cells. When [3H]TdR was used as a label in a similar experiment, only 0-3% of the label was observed to become associated with the population of nuclei from heated cells and autoradiography showed that 97% of these nuclei were not labeled. Comparable results were obtained when the labeled cells were heated and the control cells were left unlabeled. These results show that a small amount of protein (approximately 10% of the nuclear protein) will cross-migrate during nuclear isolation without affecting the net amount of protein in either population.

Cell Fractionation↗
PubMed1983

Characterization of complementary deoxyribonucleic acid and genomic deoxyribonucleic acid for the beta chain of human fibrinogen.

A total of 148 cDNAs coding for the beta chain of human fibrinogen have been identified from a human liver cDNA library employing a bovine cDNA as a probe. The largest cDNA insert contained 1932 base pairs cloned into the PstI site of plasmid pBR322. This cDNA insert contained 66 base pairs coding for a portion or all of a signal sequence, 1383 base pairs coding for 461 amino acids in the mature protein, a stop codon of TAG, a noncoding region of 431 base pairs, and a poly(A) tail of 19 base pairs. Most of the cDNA inserts coding for the beta chain were found to have a noncoding region of 98 or 167 base pairs rather than 431 base pairs at the 3'-end. The bovine cDNA for the beta chain was also employed as a probe for screening a lambda phage library containing human genomic DNA. Seven positive phage were identified. One of the phage, which contained the entire gene for the beta chain of fibrinogen, was examined by electron microscopy, and portions of its DNA sequence are presented. Seven intervening sequences were identified in the gene for the beta chain of human fibrinogen. The largest intervening sequence (approximately 1.3 kilobases) was found at the 5'-end of the gene and was located between amino acid residues 8 and 9, which are present in fibrinopeptide B. A sequence analysis of the 5'-end of the gene also indicated that the B chain of human fibrinogen contained a signal sequence of either 16, 27, or 30 amino acid residues.

Amino Acid Sequence↗
PubMed1983

Dimethyl sulfoxide alteration of collagen.

In vitro incubation of human scar in our laboratory with 99% DMSO demonstrated, by electron microscopy, the disruption of the collagen fibers. This may prove to be a useful preparatory step for selective enzymatic assault upon exuberant or undesirable scar tissue in the clinical setting. Further study of this concept is planned.

Collagen↗
PubMed1982

Sequence homology and structural comparison between the chromosomal human alpha 1-antitrypsin and chicken ovalbumin genes.

The human chromosomal alpha 1-antitrypsin gene has been cloned. This gene is approximately 5 kilobase pairs long and contains three intervening sequences in the peptide-coding region. DNA sequences coding for the amino and carboxyl termini of a alpha 1-antitrypsin have been identified. Human alpha 1-antitrypsin and chicken ovalbumin show significant sequences homology and belong to a common protein super-family. Yet the number, position and size of intervening sequences reveal that the two genes are dissimilar.

Animals↗
PubMed1981

Mosaic structure and mRNA precursors of uteroglobin, a hormone-regulated mammalian gene.

The synthesis of uteroglobin in the rabbit uterus is induced by progesterone and is repressed by estrogen which has an over-riding effect over the inducer. The dual hormonal control system offers an excellent model for studying hormonal regulation of mammalian gene expression. Using a full-length uteroglobin cDNA clone as a specific hybridization probe, recombinant lambda phages containing the entire chromosomal uteroglobin gene have been isolated from a rabbit genomic DNA library. Electronmicroscopic analysis of hybrid molecules formed between the chromosomal uteroglobin gene and uteroglobin mRNA indicated the presence of 2 intervening sequences within this gene. The mosaic structure of the uteroglobin gene has been substantiated by detailed restriction mapping and Southern hybridization. The gene is 3.0 kilobases in length to code for a mature mRNA of 465 nucleotides. Northern hybridization of poly(A)-containing RNA from 4-day-pregnant rabbit uterus with the full-length cDNA clone revealed the presence of uteroglobin mRNA precursors. The size of the largest precursor RNA species detected by the cDNA clone is the same as the entire chromosomal uteroglobin gene. The fidelity of the precursor RNAs was established by their ability to hybridize with specific intervening sequence probes. Thus the entire uteroglobin gene is expressed into primary RNA transcripts, which are subsequently processed into mature mRNA molecules by splicing.

Animals↗
PubMed1979

Phagocytosis of asbestos fibers by human pulmonary alveolar macrophages.

Human pulmonary alveolar macrophages (PAMs) were cultured for 24--72 h with varying concentrations (0--300 microgram/ml) of amosite asbestos (AS). At lower AS concentrations, (less than 100 microgram/ml) no decrease in cell viability occurred during the first 24 h of culture. Significant cytotoxicity (P less than 0.005 in all instances) was observed, however, following incubation for 24 h with higher AS concentrations (greater than 100 microgram/ml). Even following incubation with lower concentrations of AS, significant cytotoxicity (P less than 0.006 in all instances) was observed after 48 or 72 h of culture. Scanning electron microscopy (SEM) clearly illustrates the various stages of AS phagocytosis by PAMs. SEM also documented morphological changes in PAMs following AS exposure. These included increased zeiosis and the appearance of a fibrous-like material on the surface of AS fibers following initial contact with the PAM cytoplasmic membrane. Further study of the biological interactions between AS and human cells, such as PAMs, might provide valuable information regarding the etiology of AS-related lung disorders.

Adult↗
PubMed1978

Autosomal dominantly inherited adductor laryngeal paralysis--a new syndrome with a suggestion of linkage to HLA.

A family is reported with autosomal dominantly inherited congenital bilateral adductor paralysis of the larynx. This disorder has apparently not been described previously. A search for linkage in this family with the loci for 19 other genetic markers showed a suggestion of linkage with HLA and GLO, and accordingly a suggestion that the locus for this disorder may be assigned to chromosome 6.

Adolescent↗