Figure 5.—

LF1 encodes a novel protein of 804 amino acids. (A) Amino acid sequence of LF1. Underlined amino acid indicates location of lf1 amber stop codon. Sequence in boldface type is sufficient to rescue lf1 phenotype by transformation with p3.9NN plasmid (Figure 4). (B) Genomic sequence of the lf1 allele indicates a single-base-pair change from a G to a T leading to a premature stop codon at amino acid 87. (C) RNA blot analysis shows the 3.1-kb LF1 transcript is present in the lf1 mutant and (D) is not upregulated significantly after deflagellation. A total of 4–5 μg of poly(A) RNA was loaded per lane. P, predeflagellation. A cDNA fragment from the 3′ end of the LF1 gene was used as a probe. The same result was obtained with a probe of a cDNA fragment from the 5′ end of the LF1 gene (data not shown). A fragment of the CRY1 gene (encoding the ribosomal protein S14) was radiolabeled and used as a hybridization control for equal loading.