| First Author | Brigle KE | Year | 1992 |
| Journal | J Biol Chem | Volume | 267 |
| Issue | 31 | Pages | 22351-5 |
| PubMed ID | 1429588 | Mgi Jnum | J:3362 |
| Mgi Id | MGI:51875 | Doi | 10.1016/s0021-9258(18)41678-x |
| Citation | Brigle KE, et al. (1992) Insertion of an intracisternal A particle within the 5'-regulatory region of a gene encoding folate-binding protein in L1210 leukemia cells in response to low folate selection. Association with increased protein expression. J Biol Chem 267(31):22351-5 |
| abstractText | We have previously described a subline of L1210 murine leukemia cells (LL1) selected in a low level of 5-formyltetrahydrofolate which overexpresses a membrane-bound folate-binding protein (FBP1) and exhibits a rearrangement at the locus encoding this protein. Genomic clones containing the entire FBP1-encoding DNA from both L1210 and LL1 were isolated and characterized. Sequence analysis indicates that, with exception of the 5'-region, the FBP1-encoding locus in both cell lines is identical. The rearrangement in LL1 results from the insertion of an intracisternal A particle (IAP) in the head-to-head (antisense) orientation 72 base pairs (bp) upstream of the FBP1 ATG start codon. The IAP likely provides an alternative promoter for FBP1 expression which may produce a novel transcript with enhanced stability. Presence of the IAP appears to inactivate or relocate normal cis-acting regulatory sequences as expression of the FBP1 transcript in LL1 is not regulated by the folate status of the cell. |
