Figure 6.

Comparative Amino Acid Sequence Analysis of Proteins Encoded by RSF1 (Top, Amino Acids 105 to 224) and PIF3 (Bottom, Amino Acids 302 to 431) in the Region Containing the bHLH Domain.

The homology is apparent in the bHLH region but also extends ∼30 amino acids to the N terminus and 30 amino acids to the C terminus of this domain. Over these 120 amino acids, RSF1 and PIF3 are 35% identical and 50% similar. The 13-bp deletion in the rsf1 mutant causes a truncated protein of 145 amino acids that lacks the bHLH domain. Gray regions represent amino acids that are identical between RSF1 and PIF3. White type represents amino acids that are similar. The underlined region denotes the bHLH domain of the PIF3 gene. Dashes indicate amino acids absent from either the RSF1- or PIF3-encoded sequences.