Fig. 1. (A) Genomic organization of the basT and htpIV loci. Nucleotides matching the consensus sequence for a strong halobacterial promoter (indicated on top) are shaded (R = A or G; Y = C or T; W = A or T; S = G or C; N = A, C, G or T). eif2ba, putative translation initiation factor (Ng et al., 2000); htpV encodes a halobacterial transducer protein of unknown function (Rudolph et al., 1996); (B) Northern blot analysis of the BasT locus. Lanes 1 and 3, wild type; lanes 2 and 4, strain Mev-BasT (Kokoeva and Oesterhelt, 2000). Represented are the X-ray films after hybridization with radiolabeled probes. Lanes 1 and 2 were hybridized with a probe to orf1 (probe 1), and lanes 3 and 4 with a probe to basT (probe 2). Sequence positions of the probes are indicated in (A). Each lane contains 5 µg of total RNA.