title: The gap gene Krüppel of Rhodnius prolixus is required for segmentation and for repression of the homeotic gene sex comb-reduced.
abstract: The establishment of the anterior-posterior segmentation in insects requires the concerted action of a hierarchical gene network. Here, we study the orthologue of Krüppel gap gene in the hemipteran Rhodnius prolixus (Rp-Kr). We characterized its structure, expression pattern and function. The genomic sequence upstream of the Rp-Kr transcriptional unit shows a putative regulatory region conserved in the orthologue genes from Drosophila melanogaster and Tribolium castaneum. Rp-Kr expression is zygotic and it is expressed in the anterior half of the embryo (the posterior half of the egg) during the blastoderm stage and germ band formation; later, during germ band extension, it is expressed in a central domain, from T2 to A3. The Rp-Kr loss of function phenotypes shows disrupted thoracic and abdominal segmentation. Embryos with weak segmentation phenotypes show homeotic transformations, in which an ectopic tibial comb, typical of T1 leg, appears in T2, which correlates with the ectopic expression of Rp-sex-comb reduced in this leg.
authors.affiliation: Laboratorio de Genética y Genómica Funcional, Centro Regional de Estudios Genómicos, Universidad Nacional de La Plata, Avenue Calchaqui Km 23.5, Florencio Varela, Buenos Aires, Argentina; Centro de Bioinvestigaciones, Universidad Nacional del Noroeste de Buenos Aires, Pergamino, Argentina.
authors.forename: Andrés
authors.initials: A
authors.lastname: Lavore
authors.affiliation: Laboratorio de Genética y Genómica Funcional, Centro Regional de Estudios Genómicos, Universidad Nacional de La Plata, Avenue Calchaqui Km 23.5, Florencio Varela, Buenos Aires, Argentina.
authors.forename: Natalia
authors.initials: N
authors.lastname: Esponda-Behrens
authors.affiliation: Laboratorio de Genética y Genómica Funcional, Centro Regional de Estudios Genómicos, Universidad Nacional de La Plata, Avenue Calchaqui Km 23.5, Florencio Varela, Buenos Aires, Argentina.
authors.forename: Lucía
authors.initials: L
authors.lastname: Pagola
authors.affiliation: Laboratorio de Genética y Genómica Funcional, Centro Regional de Estudios Genómicos, Universidad Nacional de La Plata, Avenue Calchaqui Km 23.5, Florencio Varela, Buenos Aires, Argentina; Centro de Bioinvestigaciones, Universidad Nacional del Noroeste de Buenos Aires, Pergamino, Argentina. Electronic address: rrivera@unnoba.edu.ar.
authors.forename: Rolando
authors.initials: R
authors.lastname: Rivera-Pomar
mesh_terms: D000818:Animals; D001483:Base Sequence; D019521:Body Patterning / Q000235:genetics*; D004331:Drosophila melanogaster / Q000235:genetics; D004625:Embryo, Nonmammalian / Q000378:metabolism; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D051741:Kruppel-Like Transcription Factors / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D034622:RNA Interference; D034741:RNA, Small Interfering; D012239:Rhodnius / Q000196:embryology* / Q000235:genetics; D017422:Sequence Analysis, DNA; D014231:Tribolium / Q000235:genetics
chemical_list: D019476:Insect Proteins; D051741:Kruppel-Like Transcription Factors; D034741:RNA, Small Interfering
keywords: Gap gene; Hox regulation; Krüppel; Rhodnius; Segmentation