Biomedical subjects

R Y Huang

Publications and source records attributed to R Y Huang.

4 recordsLinked to original sources

PubMed1992

Broad-complex function during oogenesis in Drosophila melanogaster.

The Broad-Complex (BR-C) appears to encode factors that mediate ecdysone effects during the larva-adult transition. The main goal of this study was to gain insight into what roles the BR-C might play during oogenesis. The main findings are as follows. First, as determined by heteroallele studies and clonal analysis, de12 is a somatic line mutation that appears to fall into the broad domain of the BR-C. Second, the de12 mutation is associated with the insertion of the gypsy transposon at position 169.5 (Chao and Guild, Embo J, 1986, 5:143-150) in the BR-C domain. In its new context this gypsy element exhibits ovarian-specific activation. Both this gypsy activation and the de12 phenotype are partially suppressible by su(f) and su(Hw). Third, we have identified a set of transcripts that cross-hybridize with BR-C sequence spanning the gypsy insertion site (166-179). There are significant differences in these cross-hybridizing species, both in size and relative abundance, between de12 and its parent strain. Finally we have determined that in de12 there is a premature arrest of chorion gene amplification in the late stages of oogenesis.

Animals↗

PubMed1991

Cloning and structural analysis of MMCP-1, MMCP-4 and MMCP-5, three mouse mast cell-specific serine proteases.

Here we present the cloning of three novel mouse mast cell-specific serine proteases, MMCP-1, MMCP-4 and MMCP-5. A region of approximately 4 kb covering the five exons and 930 bp 5' and 280 bp 3' flanking sequences of the gene for MMCP-1 was characterized by nucleotide sequence analysis. A comparison with the corresponding region of the rat mucosal mast cell-specific protease RMCP-II is presented. cDNA clones for the mast cell proteases MMCP-4 (950 bp) and MMCP-5 (1098 bp) were isolated from a cDNA library of a connective tissue mast cell-like mouse mastocytoma cell line. All three proteases were found to belong to the family of chymotrypic serine proteases as deduced from the absence of the Asp 189 which is characteristic for all serine proteases having cleavage specificities similar to pancreatic trypsin. The active polypeptides, excluding possible post-translational glycosylations, have an Mr of 25-26 kDa. Analysis of the amino acid composition reveals a positive net charge for all three proteases MMCP-1 +3, MMCP-4 +18 and MMCP-5 +12). Based on their high sequence identity (88%) and high positive net charges (+18 and +18, respectively) we assume that the MMCP-4 is the mouse homolog to rat RMCP-I. Probes specific for each of these three highly homologous protease genes have been generated by subcloning of fragments of approximately 100 bp in length, originating from the 3' ends of the mRNA into plasmid vectors. Northern blot analysis of mRNA from a number of murine cell lines shows gene expression of these proteases to be specific for the differentiation stage of the mast cell. The MMCP-1 is expressed only at the mucosal mast cell stage and 5 only in mast cells of the connective tissue mast cell stage. These serine proteases may serve as highly specific markers in the analysis of mast cell heterogeneity, differentiation and function.

Amino Acid Sequence↗

PubMed1990

Cloning and structural analysis of a gene encoding a mouse mastocytoma proteoglycan core protein; analysis of its evolutionary relation to three cross hybridizing regions in the mouse genome.

Serglycin (SGC) is a Ser-Gly-repeat-containing protein, used as a proteoglycan core protein in the parietal yolk sac and in mast cells, where glycosaminoglycan side chains are attached to the serine residues of the repeat region. In this article, the structure of the gene SGC encoding mouse SGC is reported. The gene is divided into three exons, which are all contained within a region of approximately 13 kb. Nucleotide (nt) sequence analysis was carried out on a region of 1.2 kb upstream from the first exon. The region containing the two promoters (active in parietal yolk sac and in mast cells, respectively) was analyzed for the presence of recognition sites for known DNA-binding proteins. A number of sequences closely related to known recognition sites were found in both promoters, and one consensus octamer-binding site could be identified in the putative yolk-sac promoter. Multiple regions in the mouse genome hybridizing with DNA fragments covering the Ser-Gly repeat region have previously been described, and it has been suggested that these loci may represent other proteoglycan core proteins. Analysis of nt sequence was carried out on three out of the more than 15 of these regions present in the mouse genome. However, none of the clones analyzed was found to have any open reading frame in the region of cross-hybridization which possibly could code for a SGC protein. Instead, one of the clones was found to contain an exon encoding a highly basic protein, unrelated to SGC. Hence, no evidence was found for a multigene family of Ser-Gly-repeat-containing proteoglycan-encoding genes.

Aggrecans↗

PubMed1990

[Tardy ulnar palsy treated by anterior subcutaneous transposition].

Twenty cases of tardy ulnar palsy were treated by anterior subcutaneous transposition in the past 6 years at the Veterans General Hospital-Taichung. These cases were followed up for at least 9 months after operation. Mean duration of follow up was 39.5 months. Age distribution was from 40y/o to 72y/o, mean age was 54.5y/o. Duration of symptoms was from 2 months to 72 months, mean was 20.3 months. Eight cases were attributed to the idiopathic type. 16 cases (80%) improved after operation. Four factors were analyzed to evaluate their status as a prognostic guide: age, duration of syndrome, severity before operation and precipitating factors. Only severity before operation correlated with prognosis, but good recovery can be achieved in severe cases. Anterior subcutaneous transposition is a good method for treating tardy ulnar palsy.

Adolescent↗