title: Expression analysis of Drosophila doublesex, transformer-2, intersex, fruitless-like, and vitellogenin homologs in the parahaploid predator Metaseiulus occidentalis (Chelicerata: Acari: Phytoseiidae).
abstract: Characterization and expression analyses are essential to gain insight into sex-determination pathways in members of the Acari. Little is known about sex determination at the molecular level in the western orchard predatory mite Metaseiulus occidentalis (Arthropoda: Chelicerata: Arachnida: Acari: Phytoseiidae), a parahaploid species. In this study, eight genes previously identified as putative homologs to genes involved in the sex-determination pathway in Drosophila melanogaster were evaluated for sex-specific alternative splicing and sex-biased expression using reverse-transcriptase PCR and quantitative real-time PCR techniques, respectively. The homologs evaluated in M. occidentalis included two doublesex-like genes (Moccdsx1 and Moccdsx2), transformer-2 (Mocctra-2), intersex (Moccix), two fruitless-like genes (MoccBTB1 and MoccBTB2), as well as two vitellogenin-like genes (Moccvg1 and Moccvg2). Single transcripts of equal size were detected in males and females for Moccdsx1, Moccdsx2, Mocctra-2, Moccix, and MoccBTB2, suggesting that their pre-mRNAs do not undergo alternative splicing in a sex-specific manner. Three genes, Moccdsx1, Moccdsx2 and MoccBTB2, displayed male-biased expression relative to females. One gene, Moccix, displayed female-biased expression relative to males. Two genes, Mocctra-2 and MoccBTB1, did not display detectable differences in transcript abundance in males and females. Expression of Moccvg1 and Moccvg2 were detected in females only, and transcript levels were up-regulated in mated females relative to unmated females. To our knowledge, this represents the first attempt to elucidate expression patterns of putative sex-determination genes in an acarine. This study is an initial step towards understanding the sex-determination pathway in the parahaploid M. occidentalis.
authors.affiliation: Department of Entomology and Nematology, University of Florida, Gainesville, FL, USA, pomerantzaaron@gmail.com.
authors.forename: Aaron F
authors.initials: AF
authors.lastname: Pomerantz
authors.forename: Marjorie A
authors.initials: MA
authors.lastname: Hoy
mesh_terms: D000818:Animals; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology*; D008297:Male; D008925:Mites / Q000235:genetics / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011003:Ploidies; D019849:Sex Determination Processes; D013045:Species Specificity; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D014819:Vitellogenins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; C070369:DSX protein, Drosophila; D029721:Drosophila Proteins; C468125:IX protein, Drosophila; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; C097162:Tra protein, Drosophila; D014157:Transcription Factors; D014819:Vitellogenins; C103226:fru protein, Drosophila