RESUMO
Snakes are a vital component of wildlife resources and are widely distributed across the globe. The many-banded krait Bungarus multicinctus is a highly venomous snake found across Southern Asia and central and southern China. Snakes are an ancient reptile group, and their genomes can provide important clues for understanding the evolutionary history of reptiles. Additionally, genomic resources play a crucial role in comprehending the evolution of all species. However, snake genomic resources are still scarce. Here, we present a highly contiguous genome of B. multicinctus with a size of 1.51 Gb. The genome contains a repeat content of 40.15%, with a total length exceeding 620 Mb. Additionally, we annotated a total of 24,869 functional genes. This research is of great significance for comprehending the evolution of B. multicinctus and provides genomic information on the genes involved in venom gland functions.
RESUMO
Cerithidea tonkiniana is an amphibious gastropod mollusk that lives in brackish water habitats. In this study, the complete mitochondrial genome of Cerithidea tonkiniana collected from Guangxi, China was assembled for the first time based on the next generation sequencing. The length of this mitogenome is 15,617 base pair with a slightly biased AT content (63.1ï¼ ). This circular genome contains 13 proterin-coding genes, 22 tRNA genes, and 2 rRNA genes. Phylogenetic analysis using the 10 Cerithioidea species showed that the C. tonkiniana is closely related with Cerithidea sinensis and Cerithidea obtuse, forming the Potamididae cluster.
RESUMO
Poaching and trafficking have a substantial negative impact on the population growth and range expansion of the Chinese pangolin (Manis pentadactyla). However, recently reported activities of Chinese pangolins in several sites of Guangdong province in China indicate a promising sign for the recovery of this threatened species. Here, we re-sequence genomes of 15 individuals and perform comprehensive population genomics analyses with previously published 22 individuals. These Chinese pangolins are found to be divided into three distinct populations. Multiple lines of evidence indicate the existence of a newly discovered population (CPA) comprises entirely of individuals from Guangdong province. The other two populations (CPB and CPC) have previously been documented. The genetic differentiation of the CPA and CPC is extremely large (FST = 0.541), which is larger than many subspecies-level differentiations. Even for the closer CPA and CPB, their differentiation (FST = 0.101) is still comparable with the population-level differentiation of many endangered species. Further analysis reveals that the CPA and CPB populations separate 2.5-4.0 thousand years ago (kya), and on the other hand, CPA and CPC diverge around 25-40 kya. The CPA population harbors more runs of homozygosity (ROHs) than the CPB and CPC populations, indicating that inbreeding is more prevalent in the CPA population. Although the CPC population has less mutational load than CPA and CPB populations, we predict that several Loss of Function (LoF) mutations will be translocated into the CPA or CPB populations by using the CPC as a donor population for genetic rescue. Our findings imply that the conservation of Chinese pangolins is challenging, and implementing genetic rescue among the three groups should be done with extreme caution.