Zoological Research

498−514

Authors: Xiu-Juan Li,  Cong-Cong Qiao,  Bo-Jian Chen,  Meng-Yang Li,  Peng Chen,  Mao-Lin Huang,  Chun-Xiao Chen, Yan Liu, Han Cheng, Meng-Wan Jiang, Lu-Ye Shi, Zhen-Long Wang

Oxygen is essential for most life forms. Insufficient oxygen supply can disrupt homeostasis and compromise survival, and hypoxia-induced cardiovascular failure is fatal in many animals, including humans. However, certain species have adapted and evolved to cope with hypoxic environments and are therefore good models for studying the regulatory mechanisms underlying responses to hypoxia. Here, we explored the physiological and molecular responses of the cardiovascular system in two closely related hypoxia-adapted species with different life histories, namely, Qinghai voles (Neodon fuscus) and Brandt’s voles (Lasiopodomys brandtii), under hypoxic (10% O2 for 48 h) and normoxic (20.9% O2 for 48 h) exposure. Kunming mice (Mus musculus) were used for comparison. Qinghai voles live in plateau areas under hypoxic conditions, whereas Brandt’s voles only experience periodic hypoxia. Histological and hematological analyses indicated a strong tolerance to hypoxia in both species, but significant cardiac tissue damage and increased blood circulation resistance in mice exposed to hypoxia. Comparative transcriptome analysis revealed enhanced oxygen transport efficiency as a coping mechanism against hypoxia in both N. fuscus and L. brandtii, but with some differences. Specifically, N. fuscus showed up-regulated expression of genes related to accelerated cardiac contraction and angiogenesis, whereas L. brandtii showed significant up-regulation of erythropoiesis-related genes. Synchronized up-regulation of hemoglobin synthesis-related genes was observed in both species. In addition, differences in cardiometabolic strategies against hypoxia were observed in the rodents. Notably, M. musculus relied on adenosine triphosphate (ATP) generation via fatty acid oxidation, whereas N. fuscus shifted energy production to glucose oxidation under hypoxic conditions and L. brandtii employed a conservative strategy involving down-regulation of fatty acid and glucose oxidation and a bradycardia phenotype. In conclusion, the cardiovascular systems of N. fuscus and L. brandtii have evolved different adaptation strategies to enhance oxygen transport capacity and conserve energy under hypoxia. Our findings suggest that the coping mechanisms underlying hypoxia tolerance in these closely related species are context dependent.

524−528

Authors: Yi-Xin Chen, Yang Yu, Cheng Li, Zhi-Shu Xiao, Guo-Wei Zhou, Zhong-Jian Zhang, Xin-Wen Wang, Zuo-Fu Xiang, Jiang Chang, Ming Li

 

533−535

Authors: Ying Lu, Chang Chu, Xiao-Qing Zhang, Shu-Qiang Li, Zhi-Yuan Yao

 

538−552

Authors: Hong Zhang, Wan-Wan Zhang, Cheng-Yu Mo, Meng-Dan Dong, Kun-Tong Jia, Wei Liu, Mei-Sheng Yi

In vitro production of functional gametes can revolutionize reproduction by reducing generation intervals and accelerating genetic breeding in aquaculture, especially in fish with relatively long generations. Nevertheless, functional sperm production from in vitro-cultured spermatogonia remains a challenge in most aquaculture fish. In this study, we isolated and characterized premeiotic spermatogonia from marine four-eyed sleepers (Bostrychus sinensis), which are prone to ovotesticular or sterile testicular development, and induced the differentiation of the spermatogonia into flagellated sperm in a three-dimensional (3D) culture system. Artificial insemination indicated that the in vitro-derived sperm were capable of fertilizing mature oocytes to develop into normal larvae. Furthermore, melatonin significantly promoted spermatogonia proliferation and differentiation through the ERK1/2 signaling pathway, and thus increased the efficiency in functional sperm production. The 3D culture system and resulting functional sperm hold great promise for improving the genetic breeding of aquaculture fish.

567−585

Authors: Min Li,  Wen-Ting Chen,  Qi-Lin Zhang,  Min Liu,  Cheng-Wei Xing,  Ya Cao,  Fang-Zhen Luo,  Ming-Long Yuan

Spiders are among the most varied terrestrial predators, with highly diverse morphology, ecology, and behavior. Morphological and molecular data have greatly contributed to advances in the phylogeny and evolutionary dynamics of spiders. Here, we performed comprehensive mitochondrial phylogenomics analysis on 78 mitochondrial genomes (mitogenomes) representing 29 families; of these, 23 species from eight families were newly generated. Mesothelae retained the same gene arrangement as the arthropod ancestor (Limulus polyphemus), while Opisthothelae showed extensive rearrangement, with 12 rearrangement types in transfer RNAs (tRNAs) and control region. Most spider tRNAs were extremely truncated and lacked typical dihydrouridine or TΨC arms, showing high tRNA structural diversity; in particular, trnS1 exhibited anticodon diversity across the phylogeny. The evolutionary rates of mitochondrial genes were potentially associated with gene rearrangement or truncated tRNAs. Both mitogenomic sequences and rearrangements possessed phylogenetic characteristics, providing a robust backbone for spider phylogeny, as previously reported. The monophyly of suborder, infraorder, retrolateral tibial apophysis clade, and families (except for Pisauridae) was separately supported, and high-level relationships were resolved as (Mesothelae, (Mygalomorphae, (Entelegynae, (Synspermiata, Hypochilidae)))). The phylogenetic positions of several families were also resolved (e.g., Eresidae, Oecobiidae and Titanoecidae). Two reconstructions of ancestral web type obtained almost identical results, indicating that the common ancestor of spiders likely foraged using a silk-lined burrow. This study, the largest mitochondrial phylogenomics analysis of spiders to date, highlights the usefulness of mitogenomic data not only for providing efficient phylogenetic signals for spider phylogeny, but also for characterizing trait diversification in spider evolution.

598−600

Authors: Yan Shen, Lu-Feng Ding, Chao-Yu Yang, Fang Xu, Pak-Ming Lau, Guo-Qiang Bi

 

605−608

Authors: Jin-Wei Wu, Ru Zhang, Ya-Lin Qin, Li Wang, Ming-Bo Han, Zi-Fan Zhao, Pei Jing, Hai-Lu Sun, Song Wang, Ning Huang, Bao-Guo Li, Dong-Dong Wu, Chi Zhang, Xiao-Guang Qi

 

613−615

Authors: Tian-Zhang Song, Yong-Tang Zheng

 

634−647

Authors: Yuan Yuan,  Da-Ming Sun,  Tao Qin,  Sheng-Yong Mao,  Wei-Yun Zhu,  Yu-Yang Yin,  Jie Huang, Rasmus Heller, Zhi-Peng Li, Jun-Hua Liu, Qiang Qiu

As an important evolutionary innovation and unique organ, the rumen has played a crucial role in ruminant adaptation to complex ecological environments. However, the cellular basis of its complex morphology and function remains largely unknown. In this study, we identified eight major cell types from seven representative prenatal and postnatal rumen samples using ~56 600 single-cell transcriptomes. We captured the dynamic changes and high heterogeneity in cellular and molecular profiles before, during, and after the appearance of keratinized stratified squamous epithelium with neatly arranged papillae and functional maturity. Basal cells, keratinocytes, differentiating keratinocytes, terminally differentiated keratinocytes, and special spinous cells provided the cellular basis for rumen epithelium formation. Notably, we obtained clear evidence of two keratinization processes involved in early papillogenesis and papillae keratinization and identified TBX3 as a potential marker gene. Importantly, enriched stratum spinosum cells played crucial roles in volatile fatty acid (VFA) metabolism and immune response. Our results provide a comprehensive transcriptional landscape of rumen development at single-cell resolution, as well as valuable insight into the interactions between dietary metabolism and the rumen.

666−670

Authors: Christian Roos, Roberto Portela Miguez, Dietmar Zinner, Tilo Nadler, Van Ngoc Thinh

 

675−678

Authors: Ying-Yi Zhang, Rong-Rong Zhang, Shao-Bo Ma, Shuai-Shuai Liu, Qiang Lin, Xin Wang

 

683−686

Authors: Wu Jin, Xiao-Juan Cao, Xue-Yan Ma, Guo-Hua Lv, Gang-Chun Xu, Pao Xu, Bing Sun, Dong-Po Xu, Hai-Bo Wen

 

691−694

Authors: Xiao Zhang, Guang-Yao Lai, Giacomo Volpe, Lei Han, Patrick H. Maxwell, Long-Qi Liu, Miguel A. Esteban Yi-Wei Lai