Biomaterial Database

Differential expression of N-ras in metaplastic retinal pigmented epithelium. 1989

D K Wilcox, and J P Vergnes

Department of Ophthalmology, University of Pittsburgh School of Medicine, PA.

Changes in expression of proto-oncogenes have been suggested as a key element in controlling the proliferative and differentiated status of a cell. We studied the expression of several of these genes in proliferating normal and metaplastic RPE cells. Using cDNAs to the c-myc, N-ras and n-myc genes we performed Northern blot analysis on the cytoplasmic RNA in normal and metaplastic RPE cells. We found that proliferating normal and metaplastic RPE cells exhibit similar patterns of expression of the c-myc gene. In contrast, when compared to normal cells, proliferating metaplastic RPE cells exhibited early and abnormally high levels of a 4 kb N-ras RNA. These changes in N-ras expression precede the vitreous-induced phenotypic change from an epithelial to a fibroblastic morphology. Understanding what role, if any, the N-ras gene plays in this metaplasia may lead to a better understanding of proliferative disorders such as proliferative vitreoretinopathy.

UI	MeSH Term	Description	Entries
D008679	Metaplasia	A condition in which there is a change of one adult cell type to another similar adult cell type.
D008938	Mitosis	A type of CELL NUCLEUS division by means of which the two daughter nuclei normally receive identical complements of the number of CHROMOSOMES of the somatic cells of the species.	M Phase, Mitotic,Mitotic M Phase,M Phases, Mitotic,Mitoses,Mitotic M Phases,Phase, Mitotic M,Phases, Mitotic M
D009693	Nucleic Acid Hybridization	Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)	Genomic Hybridization,Acid Hybridization, Nucleic,Acid Hybridizations, Nucleic,Genomic Hybridizations,Hybridization, Genomic,Hybridization, Nucleic Acid,Hybridizations, Genomic,Hybridizations, Nucleic Acid,Nucleic Acid Hybridizations
D009857	Oncogenes	Genes whose gain-of-function alterations lead to NEOPLASTIC CELL TRANSFORMATION. They include, for example, genes for activators or stimulators of CELL PROLIFERATION such as growth factors, growth factor receptors, protein kinases, signal transducers, nuclear phosphoproteins, and transcription factors. A prefix of "v-" before oncogene symbols indicates oncogenes captured and transmitted by RETROVIRUSES; the prefix "c-" before the gene symbol of an oncogene indicates it is the cellular homolog (PROTO-ONCOGENES) of a v-oncogene.	Transforming Genes,Oncogene,Transforming Gene,Gene, Transforming,Genes, Transforming
D010857	Pigment Epithelium of Eye	The layer of pigment-containing epithelial cells in the RETINA; the CILIARY BODY; and the IRIS in the eye.	Eye Pigment Epithelium
D011905	Genes, ras	Family of retrovirus-associated DNA sequences (ras) originally isolated from Harvey (H-ras, Ha-ras, rasH) and Kirsten (K-ras, Ki-ras, rasK) murine sarcoma viruses. Ras genes are widely conserved among animal species and sequences corresponding to both H-ras and K-ras genes have been detected in human, avian, murine, and non-vertebrate genomes. The closely related N-ras gene has been detected in human neuroblastoma and sarcoma cell lines. All genes of the family have a similar exon-intron structure and each encodes a p21 protein.	Ha-ras Genes,Ki-ras Genes,N-ras Genes,c-Ha-ras Genes,c-Ki-ras Genes,c-N-ras Genes,ras Genes,v-Ha-ras Genes,v-Ki-ras Genes,H-ras Genes,H-ras Oncogenes,Ha-ras Oncogenes,K-ras Genes,K-ras Oncogenes,Ki-ras Oncogenes,N-ras Oncogenes,c-H-ras Genes,c-H-ras Proto-Oncogenes,c-Ha-ras Proto-Oncogenes,c-K-ras Genes,c-K-ras Proto-Oncogenes,c-Ki-ras Proto-Oncogenes,c-N-ras Proto-Oncogenes,ras Oncogene,v-H-ras Genes,v-H-ras Oncogenes,v-Ha-ras Oncogenes,v-K-ras Genes,v-K-ras Oncogenes,v-Ki-ras Oncogenes,Gene, Ha-ras,Gene, Ki-ras,Gene, v-Ha-ras,Gene, v-Ki-ras,Genes, Ha-ras,Genes, Ki-ras,Genes, N-ras,Genes, v-Ha-ras,Genes, v-Ki-ras,H ras Genes,H ras Oncogenes,H-ras Gene,H-ras Oncogene,Ha ras Genes,Ha ras Oncogenes,Ha-ras Gene,Ha-ras Oncogene,K ras Genes,K ras Oncogenes,K-ras Gene,K-ras Oncogene,Ki ras Genes,Ki ras Oncogenes,Ki-ras Gene,Ki-ras Oncogene,N ras Genes,N ras Oncogenes,N-ras Gene,N-ras Oncogene,c H ras Genes,c H ras Proto Oncogenes,c Ha ras Genes,c Ha ras Proto Oncogenes,c K ras Genes,c K ras Proto Oncogenes,c Ki ras Genes,c Ki ras Proto Oncogenes,c N ras Genes,c N ras Proto Oncogenes,c-H-ras Gene,c-H-ras Proto-Oncogene,c-Ha-ras Gene,c-Ha-ras Proto-Oncogene,c-K-ras Gene,c-K-ras Proto-Oncogene,c-Ki-ras Gene,c-Ki-ras Proto-Oncogene,c-N-ras Gene,c-N-ras Proto-Oncogene,ras Gene,ras Oncogenes,v H ras Genes,v H ras Oncogenes,v Ha ras Genes,v Ha ras Oncogenes,v K ras Genes,v K ras Oncogenes,v Ki ras Genes,v Ki ras Oncogenes,v-H-ras Gene,v-H-ras Oncogene,v-Ha-ras Gene,v-Ha-ras Oncogene,v-K-ras Gene,v-K-ras Oncogene,v-Ki-ras Gene,v-Ki-ras Oncogene
D002452	Cell Count	The number of CELLS of a specific kind, usually measured per unit volume or area of sample.	Cell Density,Cell Number,Cell Counts,Cell Densities,Cell Numbers,Count, Cell,Counts, Cell,Densities, Cell,Density, Cell,Number, Cell,Numbers, Cell
D002454	Cell Differentiation	Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.	Differentiation, Cell,Cell Differentiations,Differentiations, Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D012333	RNA, Messenger	RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.	Messenger RNA,Messenger RNA, Polyadenylated,Poly(A) Tail,Poly(A)+ RNA,Poly(A)+ mRNA,RNA, Messenger, Polyadenylated,RNA, Polyadenylated,mRNA,mRNA, Non-Polyadenylated,mRNA, Polyadenylated,Non-Polyadenylated mRNA,Poly(A) RNA,Polyadenylated mRNA,Non Polyadenylated mRNA,Polyadenylated Messenger RNA,Polyadenylated RNA,RNA, Polyadenylated Messenger,mRNA, Non Polyadenylated