One major mechanism of phase variable gene expression in prokaryotes is through inversion of the promoter element for a gene or operon. This protocol describes how to detect the promoter orientation of a phase-variable gene by PCR. This protocol, including primer design, is specific to detection of the promoter orientations of hyxR, a LuxR-like response regulator in Extraintestinal Pathogenic E...

'Human T Cell Receptor Beta Variable (TRBV) Genes', the seventh report of the 'IMGT Locus on Focus' section, comprises four tables: (1) 'Number of human germline TRBV genes at 7q35 and potential repertoire'; (2) 'Human germline TRBV genes at 7q35'; (3) 'Human TRBV orphons on chromosome 9 (9p21)', and (4) 'Human TRBV allele table'. These tables are available at the IMGT Marie-Paule page from IMG...

Both the pattern and level of rRNA gene methylation vary in the rat. This variation reflects stages in the maturation process and perhaps the level of gene expression in different tissues. We studied methylation at a common site, the inner cytosine of the sequence CCGG, by hybridizing 32P-rRNA to DNA digests obtained with endonuclease Msp I (which cleaves CCGG and CMCGG) and its isochizomer, Hp...

We have tested whether immunoglobulin light chain variable region genes are capable of directing initiation of transcription without undergoing the DNA rearrangement which creates a complete immunoglobulin gene. Two human Vk genes specifically initiated transcription in vitro at a site which is approximately 30 bases downstream of a TATA box and 20 bases upstream of the initiation codon. A Vk p...