Search PubMed⌕ Search

Biomedical subjects

R Ng

Publications and source records attributed to R Ng.

43 records · Page 3Linked to original sources
PubMedDate not supplied

A test for intron function in the yeast actin gene.

Many eukaryotic genes contain intervening sequences (IVS), but the rationale for their existence remains a mystery. Previous studies done in our laboratory demonstrated that the intron in a yeast tRNATyr gene, SUP6, does have a function. We used the same approach to determine the role of introns in nuclear genes encoding messenger RNAs. A single actin gene with one intron exists in Saccharomyces cerevisiae. The level of actin in yeast appears to be crucial to viability: either too much or too little actin inhibits growth. Therefore, small effects on synthesis of actin protein resulting from the removal of the actin gene intron would be expected to cause measurable changes in cell growth. In the present study, an intron-deleted actin gene was constructed in vitro and was used to replace the single resident actin gene in a haploid strain. Analysis of the cells carrying the intron-deleted actin gene shows that the intervening sequence is not essential for actin gene expression.

Actins↗
PubMedDate not supplied

Plasminogen activator in human breast cancer cytosols: revisited after five years.

The outcome after five years in 63 women with breast cancer was correlated with biochemical parameters (estrogen and progesterone receptors, plasminogen activator activity) determined in the cytosol of tumour specimens obtained at surgery. The information from tumour cell products and their regulatory proteins may provide additional prognostic indicators, independent of subsequent treatment.

Breast Neoplasms↗
PubMedDate not supplied

Lectin resistance and lectin binding in a rat adenocarcinoma.

Cell cultures from the R3230 AC rat mammary adenocarcinoma, when injected i.v. into F 344 rats, invariably produce multiple lung foci within 10 days. We compared the colonization potential of cultures exposed to 100 micrograms/ml medium of both Concanavalin A and Wheat Germ Agglutinin for 5 passages with the original cell line. All cell lines retained their ability to bind both lectins and to grow after subcutaneous implant; however, the lectin resistant after subcutaneous implant; however, the lectin resistant variant was found to have completely lost its capacity to nidate in the lung.

Adenocarcinoma↗