Multiple DNA sequence elements are necessary for the function of an immunoglobulin heavy chain promoter

Sequences required for the function of the mouse V1 immunoglobulin heavy chain variable-region (V/sub H/) promoter were identified by transient transfection of the normal and mutated promoters into plasmacytoma cells. The results identify four regions required for normal promoter function: (i) the octamer ATGCAAAT, previously identified by others; (ii) a heptamer, CTAATGA; (iii) a pyrimidine-rich region; and (iv) a region between positions -125 and -251 relative to the transcription start site. Sequence analysis of 19 mouse and human V/sub H/ 5' flanking regions shows that the heptamer and pyrimidine stretch are strongly conserved. The authors have also demonstrated that the octamer functions in an orientation independent manner in the V/sub H/ promoter