title: Cloning, phylogeny, and expression analysis of the Broad-Complex gene in the longicorn beetle Psacothea hilaris.
abstract: Seven isoforms of Broad-Complex (PhBR-C), in which the sequence of the zinc finger domain differed (referred to as Z1, Z2, Z3, Z2/Z3, Z4, Z5/Z6, and Z6, respectively), were cloned from the yellow-spotted longicorn beetle Psacothea hilaris. The Z1-Z4 sequences were highly conserved among insect species. The Z5/Z6 isoform was aberrant in that it contained a premature stop codon. Z6 had previously only been detected in a hemimetabola, the German cockroach Blattella germanica. The presence of Z6 in P. hilaris, and not in other holometabolous model insects such as Drosophila melanogaster or Tribolium castaneum, suggests that Z6 was lost multiple times in holometabolous insects during the course of evolution. PhBR-C expression levels in the brain, salivary gland, and epidermis of larvae grown under different feeding regimens were subsequently investigated. PhBR-C expression levels increased in every tissue examined after the gut purge, and high expression levels were observed in prepupae. A low level of PhBR-C expression was continuously observed in the brain. An increase was noted in PhBR-C expression levels in the epidermis when 4th instar larvae were starved after 4 days of feeding, which induced precocious pupation. No significant changes were observed in expression levels in any tissues of larvae starved immediately after ecdysis into 4th instar, which did not grow and eventually died.
authors.affiliation: Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 113-8657 Japan ; National Institute of Agrobiological Sciences, Tsukuba, 305-8634 Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Nagamine
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, 305-8634 Japan.
authors.forename: Takumi
authors.initials: T
authors.lastname: Kayukawa
authors.affiliation: Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 113-8657 Japan.
authors.forename: Sugihiko
authors.initials: S
authors.lastname: Hoshizaki
authors.affiliation: Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 113-8657 Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsuo
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, 305-8634 Japan.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Shinoda
authors.affiliation: Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 113-8657 Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Ishikawa
keywords: Broad-Complex; Holometabola; Psacothea hilaris; Starvation