RESUMEN
In this study, a tick intracellular symbiont, Candidatus Midichloria mitochondrii, was detected in Hyalomma anatolicum from Xinjiang, China. Morphological identification and cytochrome oxidase subunit I sequence alignment were used for molecular identification of the tick species. PCR detection further revealed the presence of endosymbiont C. M. mitochondrii in the tick. Specific primers were designed for Groel and 16S rRNA genes of C. M. mitochondrii for PCR amplification and phylogenetic analysis. To further investigate the vertical transmission characteristics of C. M. mitochondrii, specific primers were designed based on the Fabâ gene fragment to detect C. M. mitochondrii in different developmental stages and organs of the tick using qPCR. Of the 336 tick specimens collected from the field, 266 samples were identified as H. anatolicum on the basis of morphological characteristics. The gene fragment alignment results of COI confirmed that these ticks were H. anatolicum. The phylogenetic analysis showed that Groel gene of C. M. mitochondrii clustered with Midichloria strains detected in Ixodes ricinus ticks from Italy and Ixodes holocyclus ticks from Australia, with 100% sequence similarity. Furthermore, the 16S rRNA gene of C. M. mitochondrii clusters with the strains isolated from Hyalomma rufipes ticks in Italy, exhibiting the highest degree of homology. qPCR results showed that C. M. mitochondrii was present at all developmental stages of H. anatolicum, with the highest relative abundance in eggs, and lower relative abundance in nymphs and unfed males. With female tick blood feeding, the relative abundance of C. M. mitochondrii increased, and a particularly high relative abundance was detected in the ovaries of engorged female ticks. This study provides information for studying the survival adaptability of H. anatolicum, and provides data for further investigation of the mechanisms regulating tick endosymbionts in ticks, enriching the reference materials for comprehensive prevention and control of tick-borne diseases.
Asunto(s)
Ixodidae , Filogenia , ARN Ribosómico 16S , Simbiosis , Animales , Ixodidae/microbiología , Ixodidae/crecimiento & desarrollo , ARN Ribosómico 16S/genética , Femenino , Masculino , China , Chaperonina 60/genética , Ninfa/microbiología , Ninfa/crecimiento & desarrollo , Alineación de Secuencia , Complejo IV de Transporte de Electrones/genética , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/veterinaria , Reacción en Cadena de la Polimerasa , ADN Bacteriano , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
We present a field-collected Hyalomma anatolicum gynandromorph in Xinjiang, China. Compared to the normal H. anatolicum, the gynandromorphic tick was a typical bipartite protogynander: half of the tick body displayed normal female traits, whereas the other side showed normal male traits. The engorged gynandromorphic tick laid hundreds of eggs, and the eggs looked normal.