https://repositorio.ifpa.edu.br/jspui/handle/prefix/75 Thu, 26 Mar 2026 23:07:11 GMT 2026-03-26T23:07:11Z https://repositorio.ifpa.edu.br/jspui/handle/prefix/542 Título: Tityus silvestris Pocock, 1897 in Palm Trees in a Region of Central Amazon Autor(es): MARTINS, Jonas; ALMEIDA, Bruno; PROCÓPIO, Rudi Tipo: Artigo de Periódico Fri, 29 Apr 2022 00:00:00 GMT https://repositorio.ifpa.edu.br/jspui/handle/prefix/542 2022-04-29T00:00:00Z https://repositorio.ifpa.edu.br/jspui/handle/prefix/540 Título: Kinetic Activity of Chromosomes and Expression of Recombination Genes in Achiasmatic Meiosis of Tityus (Archaeotityus) Scorpions Autor(es): ALMEIDA, Bruno Rafael Ribeiro de; NORONHA, Renata Coelho Rodrigues; CARDOSO, Adauto Lima; MARTINS, Cesar; MARTINS, Jonas Gama; PROCÓPIO, Rudi Emerson de Lima; NAGAMACHI, Cleusa Yoshiko; PIECZARKA, Julio Cesar Abstract: Several species of Tityus (Scorpiones, Buthidae) present multi-chromosomal meiotic associations and failures in the synaptic process, originated from reciprocal translocations. Holocentric chromosomes and achiasmatic meiosis in males are present in all members of this genus. In the present study, we investigated synapse dynamics, transcriptional silencing by H2AX, and meiotic microtubule association in bivalents and a quadrivalent of the scorpion Tityus maranhensis. Additionally, we performed RT-PCR to verify the expression of mismatch repair enzymes involved in crossing-over formation in Tityus silvestris gonads. The quadrivalent association in T. maranhensis showed delay in the synaptic process and long asynaptic regions during pachytene. In this species, H2AX was recorded only at the chromosome ends during early stages of prophase I; in metaphase I, bivalents and quadrivalents of T. maranhensis exhibited binding to microtubules along their entire length, while in metaphase II/anaphase II transition, spindle fibers interacted only with telomeric regions. Regarding T. silvestris, genes involved in the recombination process were transcribed in ovaries, testes and embryos, without significant difference between these tissues. The expression of these genes during T. silvestris achiasmatic meiosis is discussed in the present study. The absence of meiotic inactivation by H2AX and holo/telokinetic behavior of the chromosomes are important factors for the maintenance of the quadrivalent in T. maranhensis and the normal continuation of the meiotic cycle in this species. Tipo: Artigo de Periódico Tue, 16 Aug 2022 00:00:00 GMT https://repositorio.ifpa.edu.br/jspui/handle/prefix/540 2022-08-16T00:00:00Z https://repositorio.ifpa.edu.br/jspui/handle/prefix/337 Título: Estudos citogenéticos em cromossomos holo e monocêntricos de escorpiões amazônicos Autor(es): ALMEIDA, Bruno Rafael Ribeiro de Primeiro Orientador: PIECZARKA, Julio Cesar Instituição: Universidade Federal do Pará Tipo: Tese Fri, 09 Jul 2021 00:00:00 GMT https://repositorio.ifpa.edu.br/jspui/handle/prefix/337 2021-07-09T00:00:00Z