Teleogryllus emma

Abstract The estrogen receptor-related receptors (ERRs) are a group of nuclear receptors that were originally identified on the basis of sequence similarity to estrogen receptors. The three mammalian ERR genes have been implicated in diverse physiological processes ranging from placental development to maintenance of bone density, but the function and regulation of ERRs in invertebrates are not well understood. A homologue of human ERR was isolated from the cricket Teleogryllus emma (Ohmachi and Matsumura) (Orthoptera: Gryllidae). The full-length cDNA of T. emma ERR, termed TeERR, has 1618 base pair (bp) and contains a 5′-untranslated region of 140 bp and a 3′-untranslated region of 272 bp. The open reading frame of TeERR encodes a deduced 401 amino acid peptide with a predicted molecular mass of 45.75 kilodaltons. The results of sequence alignments indicate that the TeERR protein shares an overall identity of 65%-82% with other known ERR homologues, and is most closely related to that of Nasonia vitripennis (Hymenoptera: Pteromalidae) and Apis mellifera (Apidae). Real-time quantitative reverse transcription-polymerase chain reaction was performed to compare the TeERR mRNA expression level at the whole body and gonad during T. emma development. The data revealed that TeERR mRNA is differentially expressed during T. emma development, with the highest expression level in embryos and the lowest in the body of late-instar larvae. The levels of TeERR transcripts also varied thr...

• URI: • Definition: A depression caused by erosion by water or ice. Low-lying land bordered by higher ground; especially elongate, relatively large gently sloping depressions of the Earth's surface, commonly situated between two mountains or between ranges of hills or mountains, and often containing a stream with an outlet.

Introduction Photoperiodism in crickets has been little studied. A few known examples indicate, however, that insects of this group are able to read the photoperiodic calendar. Teleogryllus species may offer suitable material for understanding the problem of climatic adaptation in various regions. The solution of such a problem seems to be essential for constructing the evolutionary pictures of their speciation and the formation of their present patterns of distribution. Divergence in climatic adaptation frequently accompanies divergence in the life cycle, and this may play an important role in reproductive isolation (Alexander and Bigelow, 1960, Bigelow, 1960a, Bigelow, 1960b, Bigelow, 1962, Masaki, 1965, Ohmachi and Masaki, 1964). The occurrence of very closely related species with different seasonal life histories seems to support this assumption (Bigelow and Cochaux, 1962, Hogan, 1965). Field crickets (Gryllinae, especially Gryllus spp.) have many advantages for field and laboratory studies of insect ecology and behavior (Bertram, 2002, Choo and Choi, 1983, Doherty and Storz, 1992, Fitzpatrick and Gray, 2001, Gray, 1999). They are widely distributed, easily collected, large in size and easily sexed. However, relatively little is known about their developmental characteristics, particularly those of Teleogryllus emma. The emma field cricket, T. emma is one of the most conspicuous and widely distributed in Korea. This species undergoes an embryonic diapause and produces ...