China-Bangladesh Scientific Cooperation Unveils the Mystery of Hilsa Fish Sex Reversal

  2月27日，孟加拉国贾格纳特大学（JNU）与中国上海海洋大学（SHOU）联合研究团队在达卡举行新闻发布会，宣布在孟加拉国国鱼——鲥鱼（Tenualosa ilisha）研究领域取得三项突破性成果，这标志着中孟两国在鲥鱼生物学特性、资源保护及可持续管理方面的研究迈上了新台阶，更凸显了“一带一路”倡议下国际科研合作的显著成效。

  On February 27, a joint research team from Jagannath University (JNU) in Bangladesh and Shanghai Ocean University (SHOU) in China held a press conference in Dhaka to announce three groundbreaking achievements in the study of the national fish of Bangladesh, Hilsa (Tenualosa ilisha). This marks a new milestone in China-Bangladeshi research on the biological characteristics, resource conservation, and sustainable management of Hilsa, highlighting the remarkable success of international scientific cooperation under the Belt and Road Initiative.

  此次发布会特别介绍了三位毕业于上海海洋大学的孟加拉国学者——Md Rashedur Rahman博士、Kishor Kumar Sarker博士和Anirban Sarker博士的研究成果。他们的研究分别聚焦于孟加拉鲥鱼性别逆转机制、全基因组测序及群体基因组学，为孟加拉鲥鱼的繁殖管理、遗传特性解析及资源保护提供了重要科学依据。

  The press conference specifically introduced the research achievements of three Bangladeshi scholars—Dr. Md Rashedur Rahman, Dr. Kishor Kumar Sarker, and Dr. Anirban Sarker—who graduated from Shanghai Ocean University. Their studies focus on the sex reversal mechanism of Hilsa, whole-genome sequencing, and population genomics, respectively, providing important scientific evidence for the reproductive management, genetic analysis, and resource conservation of Hilsa in Bangladesh.

鲥鱼性逆转现象首次揭示

 The Phenomenon of Hilsa Fish Sex Reversal Revealed for the First Time

  孟加拉鲥鱼，作为孟加拉国的国宝物种，不仅是该国渔业经济的支柱，也是生态系统中不可或缺的一环，它象征着孟加拉国丰富的自然资源与文化传承。与此同时，孟加拉鲥鱼作为最接近中国鲥鱼（T. reevesii）的物种，承载着中孟两国在水产养殖与生物多样性保护领域的共同愿景。此次研究成果的发布，不仅为孟加拉鲥鱼的保护与可持续利用提供了科学依据，也为全球海洋资源的可持续管理树立了典范。

  研究团队通过对帕德玛河、梅克纳河和孟加拉湾六个地区收集的203条孟加拉鲥鱼样本进行分析，首次发现其中7条样本的生殖组织中同时存在精子和卵子，证实了孟加拉鲥鱼的性逆转现象。研究表明，孟加拉鲥鱼在生命的第一年以雄性身份繁殖，随后迁往海洋觅食，并在海洋中逐渐转变为雌性，第二年返回河流繁殖。这一发现为理解孟加拉鲥鱼的完整生命周期、繁殖策略及性转变机制提供了重要科学依据。

  As the national treasure of Bangladesh, Hilsa not only serves as a pillar of the country's fisheries economy but also plays an indispensable role in the ecosystem, symbolizing Bangladesh’s rich natural resources and cultural heritage. Moreover, as the species most closely related to the Chinese Hilsa (T. reevesii), the Bangladeshi Hilsa embodies the shared vision of China and Bangladesh in the fields of aquaculture and biodiversity conservation.

  The release of this research achievement not only provides a scientific basis for the conservation and sustainable utilization of Bangladeshi Hilsa but also sets a global example for sustainable marine resource management. The research team analyzed 203 Hilsa samples collected from six regions, including the Padma River, the Meghna River, and the Bay of Bengal. For the first time, they discovered that the reproductive tissues of seven samples contained both sperm and eggs, confirming the phenomenon of sex reversal in Bangladeshi Hilsa.

  The study revealed that Hilsa initially reproduces as males in the first year of life before migrating to the ocean to feed. While in the marine environment, they gradually transition into females and return to rivers for spawning in the second year. This groundbreaking discovery provides crucial scientific evidence for understanding the complete life cycle, reproductive strategy, and sex transition mechanisms of Bangladeshi Hilsa.

全基因组测序揭示孟加拉鲥鱼独特特性

单一种群威胁孟加拉鲥鱼生存

Whole-Genome Sequencing Reveals Unique Characteristics of Bangladeshi Hilsa
Single Population Threatens the Survival of Bangladeshi Hilsa

  研究团队还完成了孟加拉鲥鱼的全基因组测序，其完整性和质量超过了此前来自印度和孟加拉国的相关数据。研究人员通过对14条孟加拉鲥鱼的九种不同组织进行RNA测序，进一步揭示了孟加拉鲥鱼独特油性质地和浓郁风味背后的遗传机制。所有DNA和RNA数据均已存储在美国国家生物技术信息中心（NCBI）的公共数据库中，为未来研究提供了宝贵资源。  

  The research team also completed the whole-genome sequencing of Bangladeshi Hilsa, achieving greater completeness and quality than previous data from India and Bangladesh. By conducting RNA sequencing on nine different tissues from 14 Hilsa specimens, researchers further uncovered the genetic mechanisms behind the species' unique oily texture and rich flavor. All DNA and RNA data have been stored in the public database of the National Center for Biotechnology Information (NCBI) in the United States, providing a valuable resource for future research.

  同时，研究结果表明，孟加拉国的鲥鱼属于单一种群，遗传多样性较低，这对其生存构成了严重威胁。研究团队警告，如果这一种群面临气候或污染相关的灾难，可能会完全灭绝。因此，建立综合管理系统并开展大规模的公众意识活动，已成为保护孟加拉鲥鱼的迫切需求。

  At the same time, the research results indicate that the Hilsa population in Bangladesh is a single genetic group with low genetic diversity, which poses a serious threat to its survival. The research team warned that if this population faces climate-related or pollution-related disasters, it could face complete extinction. Therefore, establishing a comprehensive management system and conducting large-scale public awareness campaigns have become urgent needs for the conservation of Bangladeshi Hilsa.

  上海海洋大学水产与生命学院常务副院长黄旭雄在发布会上表示：“这些研究成果不仅深化了我们对孟加拉鲥鱼生物学特性的理解，也为全球水产养殖和海洋经济发展提供了新的科学支撑。而对于孟加拉鲥鱼资源，我们不能仅仅停留在研究层面，更需要在后续实现对孟加拉鲥鱼资源的合理开发利用，将科研成果转化为实际生产力，促进孟加拉国渔业经济发展，这也是我们持续推进合作的重要目标。我们期待未来与贾甘纳特大学在更多领域开展合作，共同探索蓝色经济的发展路径，为全球海洋资源的可持续利用贡献力量。”

  At the press conference, HUANG Xuxiong, Executive Deputy Dean of the College of Fisheries and Life Science at Shanghai Ocean University, stated: "These research results not only deepen our understanding of the biological characteristics of Bangladeshi Hilsa but also provide new scientific support for global aquaculture and marine economic development. As for the resources of Bangladeshi Hilsa, we cannot just stay at the research level. It is crucial to achieve the rational development and utilization of these resources in the future, transforming scientific findings into practical productivity to promote the development of Bangladesh's fisheries economy. This is also an important goal for our continued cooperation. We look forward to collaborating with Jagannath University in more fields, jointly exploring the development path of the blue economy, and contributing to the sustainable use of global marine resources."

中孟科研合作助力可持续发展

 China-Bangladesh Scientific Cooperation Supports Sustainable Development

  自2016年以来，上海海洋大学与贾格纳特大学在水产养殖、种质资源保护及海洋生态监测等领域开展了深入合作。2019年两校签署谅解备忘录和合作协议，此次研究成果的取得，正是两校长期合作的结晶。有意义的是此次新闻发布会介绍科研成果的三位博士均毕业于上海海洋大学李晨虹教授分子系统与生态实验室。李晨虹教授表示：“这项研究是近10年努力的结果，是三届孟加拉留学生的传承，忘不了无数个在孟加拉湾野外辛苦工作的日夜和在上海海洋大学实验室苦干的夜晚。我们希望通过这些成果为孟加拉鲥鱼的保护与可持续利用提供科学依据，也希望两校教育合作能结出更多丰硕的成果。”贾格纳特大学副校长Md. Rezaul Karim教授也对研究团队的贡献表示高度赞扬，并期待这些发现能为国家层面的保护工作。

  Since 2016, Shanghai Ocean University and Jagannath University have engaged in extensive cooperation in areas such as aquaculture, germplasm resource conservation, and marine ecological monitoring. In 2019, the two universities signed a memorandum of understanding and a cooperation agreement, and the research achievements announced are the result of their long-term collaboration. Notably, the three Ph.D. researchers who presented the scientific findings at the press conference are all graduates of the Molecular Systematics and Ecology Laboratory led by Professor LI Chenhong at Shanghai Ocean University.

  Professor LI Chenhong remarked, "This research is the result of nearly 10 years of effort, representing the legacy of three generations of Bangladeshi students. We will never forget the countless nights spent working hard in the Bay of Bengal and the long hours spent in the laboratory at Shanghai Ocean University. We hope that these findings provide scientific evidence for the conservation and sustainable use of Bangladeshi Hilsa, and we also look forward to the fruitful results of further educational collaboration between our universities."

  Professor Md. Rezaul Karim, Vice Chancellor of Jagannath University, also highly praised the contributions of the research team and expressed hope that these discoveries would support national-level conservation efforts.