Project description:The mitogenome sequence of a marine gastropod, Umbonium thomasi (Crosse, 1863) (Trochida, Trochidae), was determined first in the genus Umbonium. The assembled mitogenome, consisting of 15,998?bp in length, has 13 protein-coding genes, 22 transfer RNA genes, and two ribosomal RNA genes. The order and structure of the genes are similar to those of other Trochid species. The overall base composition of mitogenome is 34.8% A, 22.1% C, 14.0% G, and 29.1% T with an A?+?T bias of 64%. The complete mitogenome of U. thomasi provides essential and important DNA molecular data for further phylogenetic and evolutionary analysis of marine gastropods.
Project description:The voles of the Microtus thomasi/M. atticus species complex demonstrate a remarkable variability in diploid chromosomal number (2n = 38-44 chromosomes) and sex chromosome morphology. In the current study, we examined by in situ hybridization the topology of four satellite DNA motifs (Msat-160, Mth-Alu900, Mth-Alu2.2, TTAGGG telomeric sequences) and two transposons (LINE, SINE) on the karyotypes of nine chromosome races (i.e., populations with unique cytogenetic traits) of Microtus thomasi, and two chromosomal races of M. atticus. According to the topology of the repetitive DNA motifs, we were able to identify six types of biarmed chromosomes formed from either Robertsonian or/and tandem fusions. In addition, we identified 14 X chromosome variants and 12 Y chromosome variants, and we were able to reconstruct their evolutionary relations, caused mainly by distinct mechanisms of amplification of repetitive DNA elements, including the telomeric sequences. Our study used the model of the Microtus thomasi/M. atticus species complex to explore how repetitive centromeric content can alter from chromosomal rearrangements and can shape the morphology of sex chromosomes, resulting in extensive inter-species cytogenetic variability.
| S-EPMC8227428 | biostudies-literature
Project description:Sequence capture for R. sinicus and R. thomasi
Project description:The Thomas's horseshoe bat (Rhinolophus thomasi) is restricted to southeast Asia and few studies have been conducted on this species. Here we characterized the complete mitochondrial genome of R. thomasi using next-generation sequencing and Sanger sequencing. The whole mitogenome is 16,899 bp in length and contains 22 tRNA, 2 rRNA, 13 protein-coding genes and a non-coding control region. The tissue used in this study was taken from a sample collected 13 years ago and the genomic DNA was seriously degraded. Our study adds to a growing number of studies indicating that next-generation sequencing is powerful in generating genetic/genomic resources from museum samples.
| S-EPMC7800769 | biostudies-literature
Project description:Bacterial diversity associated with a newly discovered sponge Cliona thomasi