Novel RBPJ transcripts identified in human amniotic fluid cells.
The NOTCH signaling pathway plays important roles in stem cell maintenance, cell-fate determination and differentiation during development. Following ligand binding, the cleaved NOTCH intracellular domain (NICD) interacts directly with the recombinant signal binding protein for immunoglobulin kappa J region (RBPJ) transcription factor and the resulting complex targets gene expression in the nucleus. To date, four human RBPJ isoforms have been described in Entrez Gene, varying in the first 5'coding exons. Using an improved protocol, we were able to further identify all four known and five novel RBPJ transcript variants in human amniotic fluid (AF) cells, a cell type known for its stem cell characteristics. In addition, we used human embryonal carcinoma (EC) NTera2/D1 (NT2) cells and NT2-derived neuron and astrocytes to compare the expression pattern of RBPJ transcripts. Further examination of RBPJ transcripts showed that the novel splice variants contain open reading frames in-frame with the known isoforms, suggesting that they can putatively generate similar function proteins. All known and novel RBPJ transcripts contain the putative nuclear localization signal (NLS), an important component of RBPJ-mediated gene regulation.
Jezierski
Anna
A
Neurogenesis and Brain Repair, Neurobiology Program, Institute for Biological Sciences, National Research Council Canada, Building M-54, 1200 Montreal Road, Ottawa, Canada.
Ly
Dao
D
Smith
Brandon
B
Smith
Cathie
C
Tremblay
Roger
R
Gruslin
Andrée
A
Sikorska
Marianna
M
Bani-Yaghoub
Mahmud
M
D000653:Amniotic Fluid / Q000166:cytology* / Q000378:metabolism*; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D006801:Humans; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein / Q000235:genetics*; D007150:Immunohistochemistry; D020033:Protein Isoforms / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; D020033:Protein Isoforms; C497570:RBPJ protein, human