title: A genome-wide identification and analysis of the basic helix-loop-helix transcription factors in the ponerine ant, Harpegnathos saltator.
abstract: BACKGROUND
  The basic helix-loop-helix (bHLH) transcription factors and their homologs form a superfamily that plays essential roles in transcriptional networks of multiple developmental processes. bHLH family members have been identified in over 20 organisms, including fruit fly, zebrafish, human and mouse.
  
  
  RESULTS
  In this study, we conducted a genome-wide survey for bHLH sequences, and identified 57 bHLH sequences encoded in complete genome sequence of the ponerine ant, Harpegnathos saltator. Phylogenetic analysis of the bHLH domain sequences classified these genes into 38 bHLH families with 23, 14, 10, 1, 8 and 1 members in group A, B, C, D, E and F, respectively. The number of PabHLHs (ponerine ant bHLHs) with introns is higher than many other insect species, and they are found to have introns with average lengths only inferior to those of pea aphid. In addition, two H. saltator bHLHs named PaCrp1 and PaSide locate on two separate contigs in the genome.
  
  
  CONCLUSIONS
  A putative full set of PabHLH genes is comparable with other insect species and genes encoding Oligo, MyoRb and Figα were not found in genomes of all insect species of which bHLH family members have been identified. Moreover, in-family phylogenetic analyses indicate that the PabHLH genes are more closely related with Apis mellifera than others. The present study will serve as a solid foundation for further investigations into the structure and function of bHLH proteins in the regulation of H. saltator development.
authors.affiliation: Institute of Life Sciences, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, PR, China
authors.forename: Ake
authors.initials: A
authors.lastname: Liu
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Chunwang
authors.initials: C
authors.lastname: Dang
authors.forename: Debao
authors.initials: D
authors.lastname: Zhang
authors.forename: Huifang
authors.initials: H
authors.lastname: Song
authors.forename: Qin
authors.initials: Q
authors.lastname: Yao
authors.forename: Keping
authors.initials: K
authors.lastname: Chen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001000:Ants / Q000235:genetics* / Q000378:metabolism; D051792:Basic Helix-Loop-Helix Proteins / Q000737:chemistry / Q000235:genetics*; D004331:Drosophila melanogaster / Q000235:genetics; D049750:Genome, Insect / Q000235:genetics*; D055106:Genome-Wide Association Study; D007438:Introns; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment
chemical_list: D051792:Basic Helix-Loop-Helix Proteins