In this study, 14 CcHsf genes were identified and characterized from the current pigeonpea genome project. Semi-quantitative RT-PCR studies using primers designed from soybean Hsf sequence information in pigeon pea. (When designing primers from soy, did you check for redundancy?) show that they should contain more hsf and that the Hsf of pigeon pea and soy are very similar. Once the genome sequence is available, you will no longer need the above information.) All predicted CcHsf genes had a conserved Hsf-like DNA binding domain, indicating that it is the most conserved among the different areas of Hsf. This is in agreement with Arabidopsis Hsfs where the DNA binding domain is highly conserved (IRRK--), (Nover et al. 2001; Scharf et al. 2012). Neither the NLS nor the NES, which are important for maintaining the intracellular distribution of Hsfs between the nucleus and the cytoplasm (Lick et al. 1997, Baniwal et.al 2004), were found in our predicted sequence. Since these are partial sequence signatures, the full structure can only be inferred once the full sequence information is available. Phylogenetic analysis of Hsfs in pigeon pea, soybean, medicago and Arabidopsis indicated that CcHsfs are more closely related to GmHsfs than to MtHsfs and AtHsfs. In a similar report (Soares-Cavalcanti et al. 2012), structural similarity was also reported with respect to Hsfs from soybean, lotus and medicago. They reported evolutionary consistency between Hsf groups, indicating the high degree of similarity in this protein family. Interestingly, MEME analysis of HsfA-1d showed that the distribution of the CcHsfA-1d motif is distinct from that of soybean, medicago, and Arabidopsis. Therefore, CcHsfA-1d might interact with other proteins in a different manner than its...... middle of article ...... hsfs are currently not fully sequenced. Completion of these sequences will help in better structure elucidation compared to other legumes. According to this study, pigeon pea hosts approximately 23 hsfs. This is a small number considering sobean has approximately 65 hsfs, making it one of the largest plants ever discovered. It is necessary to understand whether these many elements are necessary to confer thermotolerance. Given the proximity between pigeon pea and soybeans, it is also expected that more soybeans will be discovered. Since pigeon pea is more tolerant of high temperatures than pigeon pea, it will be interesting to note the composition of hsf in this plant. This study, however, forms the basis for further investigations of hsfs in pigeon pea and the differential expression of CcHsfA-2 requires further characterization as it provides a unique situation under heat stress..