A family of fibronectin mRNAs in human normal and transformed cells.
Previously, two fibronectin mRNAs, generated by alternative splicing of the extra domain (ED) and type III connecting segments (IIICS) sequences, have been described in a human transformed cell line and in human liver, respectively. We now report on a family of fibronectin mRNAs identified by Northern blotting analysis in two normal human fibroblast strains (HEL 299 and Flow 7000) and five transformed cell lines (8387 and HT-1080, fibrosarcomas; G-361, melanoma; JEG-3, choriocarcinoma; and RD, rhabdomyosarcoma). Seven different fibronectin mRNA forms with electrophoretic mobilities ranging between 8.6 and 7.7 kb were identified. Each cell line contains three (HEL 299, Flow 7000 and 8387) or two (HT-1080, G-361, JEG-3 and RD) fibronectin mRNAs species with characteristic size. In all cell lines we detected one fibronectin mRNA form which lacks the ED sequence (ED- fibronectin mRNA) and one or two fibronectin mRNAs containing it (ED+ fibronectin mRNA). These data show that the presence of ED+ and ED- fibronectin mRNAs is a general feature of all cells tested. Moreover, the fibronectin mRNA pattern is characteristic of the cell type analyzed, suggesting the occurrence of specifically programmed splicing mechanisms in each cell line.
D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D005353:Fibronectins / Q000235:genetics*; D006367:HeLa Cells / Q000378:metabolism; D006801:Humans; D009369:Neoplasms / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D012326:RNA Splicing; D012333:RNA, Messenger / Q000235:genetics* / Q000302:isolation & purification
D005353:Fibronectins; D012333:RNA, Messenger