Integrative zoology最新文献

The role of miRNAs in the regulation of seasonal reproduction in rodents, particularly in relation to photoperiod changes, is still poorly understood. Previous studies on miRNA transcriptomes of striped hamster (Cricetulus barabensis) testes have indicated that the photoperiodism of testes, especially apoptosis, may be influenced by miRNAs. As a functional miRNA, cba-miR-222-3p in striped hamster testes exhibits suppression under a short photoperiod. To elucidate the potential role of testicular cba-miR-222-3p in the seasonal reproduction of striped hamsters, we exposed male striped hamsters to different photoperiods or injected miRNA agomir into the testes and observed the effects of these treatments, particularly some indicators related to apoptosis. The results showed that the levels of apoptosis in the testes increased in short daylength, accompanied by a significant decrease in cba-miR-222-3p expression and an increase in TRAF7 expression. Dual luciferase reporter assays verified the targeting relationship between cba-miR-222-3p and TRAF7 predicted by bioinformatics. In addition, the expression of TRAF7 decreased in the testes, which injected miRNA agomir, leading to inhibition of apoptosis, and the expression of key genes (MEKK3, p38, p53) in the downstream MAPK signaling pathway of TRAF7 was suppressed. These results suggest that short daylength induces testicular apoptosis in striped hamsters, and one possible mechanism is that the decreased expression of miR-222-3p in testes reduces the repression of TRAF7 translation, thereby activating the MAPK pathway and affecting the level of testicular apoptosis. These findings reveal the potential role of miR-222-3p in animal reproduction and provide new insights into the regulation of rodent populations.

Agricultural ecosystem formation and evolution depend on interactions and communication between multiple organisms. Within this context, communication occurs between microbes, plants, and insects, often involving the release and perception of a wide range of chemical cues. Unraveling how this information is coded and interpreted is critical to expanding our understanding of how agricultural ecosystems function in terms of competition and cooperation. Investigations examining dual interactions (e.g. plant-microbe, insect-microbe, and insect-plant) have resolved some basic components of this communication. However, there is a need for systematically examining multitrophic interactions that occur simultaneously between microorganisms, insects, and plants. A more thorough understanding of these multitrophic interactions has been made possible by recent advancements in the study of such ecological interactions, which are based on a variety of contemporary technologies such as artificial intelligence sensors, multi-omics, metabarcoding, and others. Frequently, these developments have led to the discovery of startling examples of each member manipulating the other. Here, we review recent advances in the understanding of bottom-up chemical communication between microorganisms, plants, and insects, and their consequences. We discuss the components of these "chemo-languages" and how they modify outcomes of multi-species interactions across trophic levels. Further, we suggest prospects for translating the current basic understanding of multitrophic interactions into strategies that could be applied in agricultural ecosystems to increase food safety and security.

The soybean pod borer, Leguminivora glycinivorella (Matsumura), is an important tortricid pest species widely distributed in most parts of China and its adjacent regions. Here, we analyzed the genetic diversity and population differentiation of L. glycinivorella using diverse genetic information including the standard cox1 barcode sequences, mitochondrial genomes (mitogenomes), and single-nucleotide polymorphisms (SNPs) from genotyping-by-sequencing. Based on a comprehensive sampling (including adults or larvae of L. glycinivorella newly collected at 22 of the total 30 localities examined) that covers most of the known distribution range of this pest, analyses of 543 cox1 barcode sequences and 60 mitogenomes revealed that the traditionally recognized and widely distributed L. glycinivorella contains two sympatric and widely distributed genetic lineages (A and B) that were estimated to have diverged ∼1.14 million years ago during the middle Pleistocene. Moreover, low but statistically significant correlations were recognized between genetic differentiation and geographic or environmental distances, indicating the existence of local adaptation to some extent. Based on SNPs, phylogenetic inference, principal component analysis, fixation index, and admixture analysis all confirm the two divergent sympatric lineages. Compared with the stable demographic history of Lineage B, the expansion of Lineage A had possibly made the secondary contact of the two lineages probable, and this process may be driven by the climate fluctuation during the late Pleistocene as revealed by ecological niche modeling.

This study thoroughly examines biodiversity and aquatic ecosystems across 14 sampled sites within the Shitou River basin by utilizing environmental DNA technology. Through integrated analysis and high-throughput sequencing, the study elucidates a diverse array of biodiversity, encompassing 27 fish species and 341 freshwater benthic macroinvertebrates (FBM) species. Using various biodiversity indices, we found significant differences in diversity and stability across different environments. Regions with more complex habitats had higher species richness and evenness. Further analyses showed complex relationships between diversity metrics for FBM and fish, indicating potential interactions between these groups. The standardized mean score (SMS) was developed to aid in the assessment of water quality. Specifically, SMS scoring revealed that sites STH3, STH4, and STH14 excelled across multiple dimensions, earning an "Excellent" rating, while site STH12 was rated as "Poor" due to subpar performance across several metrics. This project not only enhances current understanding regarding aquatic ecological dynamics but also establishes a strong foundation for detailed environmental evaluation and monitoring, aligned with the priorities of contemporary ecological management and caution.

How organisms respond to complex environments is one of the unsolved problems in ecology. Life history patterns of a species provide essential information on how different populations may respond and adapt to environmental changes. Compared to typical seasonal breeders, which have limited distributions, the worldwide distribution of brown rats (Rattus norvegicus) across highly complex and divergent habitats suggests they exhibit exceptional adaptiveness. However, the difference in physiological mechanisms by which brown rats respond and adapt to markedly different environments is seldom investigated. Here, we reveal a significant divergence in reproductive seasonality and environmental responses between two brown rat subspecies: one subspecies, R. n. caraco, lives in the temperate zone, and another subspecies, R. n. norvegicus, lives in the subtropical region. Although R. n. caraco displayed a significantly higher reproductive seasonality than R. n. norvegicus, both subspecies adapted to sub-optimal breeding conditions mainly by regulating the seminal vesicle rather than testis development. Especially in responding to severe winter conditions in high-latitude regions, bodyweight-dependent recovery of testicular development in adults enables R. n. caraco to initiate reproduction more rapidly when conditions are suited. These findings elucidate a regulatory process of how brown rats live as opportunistic breeders by benefiting from enhanced semen production.

Variations in skin structures can possibly reflect local adaptation to distinct environmental factors. As the primary interface with the surrounding environment, amphibian skin undergoes phenotypic innovations that play a key role in protection, water absorption, and respiration. However, the effects of environmental factors on skin structures have been examined in only a limited number of species. Here, we conducted a comparative analysis of the skin structures of 102 Chinese anuran species across varying geographical distributions and habitat types. Our results revealed that the total volume of granular glands and capillary density in the dorsal skin significantly increased with increasing latitude. We also found that the thickness of calcified layers in both dorsal and ventral skin was positively correlated with annual temperature and negatively correlated with humidity. Additionally, terrestrial species exhibited the largest dorsal granular gland, whereas arboreal species had the smallest one. Likewise, the largest dorsal mucous gland was observed in aquatic species, while the smallest was found in terrestrial species. These results highlighted the importance of understanding the relationship between skin phenotypes and environmental variables and thus providing conservation strategies based on the evolutionary adaptations in anurans. Our study can contribute to the broader knowledge of evolutionary biology in anurans by demonstrating how specific skin traits are linked to survival and fitness across various ecological contexts.

Chiroptera (bats) presents a fascinating model due to its remarkable variation in chromosome numbers, which range from 14 to 62. This astonishing diversity makes bats an excellent subject for studying chromosome evolution. The black-bearded tomb bat (Taphozous melanopogon) occupies a pivotal phylogenetic position within Chiroptera, emphasizing its crucial role in the systematic examination of bat chromosome evolution. In this study, we present the first chromosome-level genome of T. melanopogon within the family Emballonuridae. Together with previously published genomes, we construct a strongly supported phylogenetic tree of bats, which supports that Emballonuridae forms a basal group within Yangochiroptera. Furthermore, we reconstruct ancestral karyotypes at key nodes along the bat phylogeny and conduct a synteny analysis among the genomes of 12 bat species. Our findings identified evolutionary breakpoint regions (EBRs) that are of particular interest. Notably, some bat genomes exhibit an enrichment of genes related to host defense against microbial pathogens within EBRs. Remarkably, one species possesses multiple copies of some β-defensin genes, while six other species have experienced the loss of some β-defensin genes due to EBRs. Furthermore, some olfactory receptor genes are located in EBRs of 12 species, 4 of which have a significant enrichment in sensory perception of smell. Together, our comparative genomic analysis underscores the potential link between chromosome rearrangements and the adaptation of bats to defend against microbial pathogens.

Many plants exhibit a canopy seed bank, where seeds persist within the canopy for prolonged periods, gradually descending over time and potentially influencing seed predation and animal-mediated dispersal. However, the impact of delayed seed drop on animal predation and seed dispersal remains unclear. We used Chinese Armand pine seeds to simulate delayed seed drop of the canopy seed bank by releasing 7800 pine seeds in both winter and the following summer over 2 years, tracking their fates to investigate its effect on seed predation and dispersal by rodents in a pine plantation in southwest China. Results showed significant seasonal differences in seed fate. In summer, seeds experienced higher predation rates (62.08% vs 3.80% in winter) and lower scatter-hoarding rates (4.18% vs 15.40% in winter). Additionally, seeds in summer were dispersed farther (4.20 m vs. 3.56 m in winter) and primarily formed single-seed caches, as opposed to multi-seed caches in winter. Although delayed seed drop increased immediate predation risks, favorable summer conditions allowed for rapid germination, reducing long-term exposure to predation. In conclusion, while delayed seed drop increases immediate predation risks and reduces caching, it concurrently enhances dispersal distances and reduces cache size.

Diamondback terrapins (Malaclemys terrapin centrata) exhibit strong environmental adaptability and live in both freshwater and saltwater. However, the genetic basis of this adaptability has not been the focus of research. In this study, we successfully constructed a ∼2.21-Gb chromosome-level genome assembly for M. t. centrata using high-coverage and high-depth genomic sequencing data generated on multiple platforms. The M. t. centrata genome contains 25 chromosomes and the scaffold N50 of ∼143.75 Mb, demonstrating high continuity and accuracy. In total, 53.82% of the genome assembly was composed of repetitive sequences, and 22 435 protein-coding genes were predicted. Our phylogenetic analysis indicated that M. t. centrata was closely related to the red-eared slider turtle (Trachemys scripta elegans), with divergence approximately ∼23.6 million years ago (Mya) during the early Neogene period of the Cenozoic era. The population size of M. t. centrata decreased significantly over the past ∼14 Mya during the Cenozoic era. Comparative genomic analysis indicated that 36 gene families related to ion transport were expanded and several genes (AQP3, solute carrier subfamily, and potassium channel genes) underwent specific amino acid site mutations in the M. t. centrata genome. Changes to these ion transport-related genes may have contributed to the remarkable salinity adaptability of diamondback terrapin. The results of this study not only provide a high-quality reference genome for M. t. centrata but also elucidate the possible genetic basis for salinity adaptation in this species.

The family Erinaceidae encompasses 27 extant species in two subfamilies: Erinaceinae, which includes spiny hedgehogs, and Galericinae, which comprises silky-furred gymnures and moonrats. Although they are commonly recognized by the general public, their phylogenetic history remains incompletely understood, and several species have never been included in any molecular analyses. Additionally, previous research suggested that the species diversity of Erinaceidae might be underestimated. In this study, we sequenced the mitochondrial genomes of 29 individuals representing 18 erinaceid species using 18 freshly collected tissue and 11 historical museum specimens. We also integrated previously published data for a concatenated analysis. We aimed to elucidate the evolutionary relationships within Erinaceidae, estimate divergence times, and uncover potential underestimated species diversity. Our data finely resolved intergeneric and interspecific relationships and presented the first molecular evidence for the phylogenetic position of Mesechinus wangi, Paraechinus micropus, and P. nudiventris. Our results revealed a sister relationship between Neotetracus and Neohylomys gymnures, as well as a sister relationship between Hemiechinus and Mesechinus, supporting previous hypotheses. Additionally, our findings provided a novel phylogenetic position for Paraechinus aethiopicus, placing it in a basal position within the genus. Furthermore, our study uncovered cryptic species diversity within Hylomys suillus as well as in Neotetracus sinensis, Atelerix albiventris, P. aethiopicus, and Hemiechinus auratus, most of which have been previously overlooked.