"甲殼類動物的血細胞參與許多重要的免疫反應，其數量的多寡會影響到免疫力的 強弱，因此血細胞數的恆定對維持一定程度的免疫力是必須的。有許多因素會造 成血細胞數的降低，然而造血作用卻是提供新細胞的唯一來源，因此深入研究造 血作用能讓我們對甲殼類動物的免疫防禦機制有進一步的了解。與其他模式動物 相較，甲殼類動物目前僅有少數的造血相關基因在螯蝦中被發現。在果蠅與哺乳 動物中的研究顯示，不同動物的造血過程雖有所不同，但一些重要的調控基因卻 是具有同源性。因此，我們認為白蝦重要的造血相關基因應該亦是如此，而從演 化的角度來看，白蝦與果蠅的相似性應該會更高。甲殼類動物的造血作用在造血 組織(Hematopoietic tissue, HPT)中進行。藉由次世代定序，我們已建立了白蝦 HPT 和血細胞的轉錄體資料庫，經由胺基酸序列比對後，我們發現到有一些基因序列 的確是與果蠅造血相關基因具有很高的相似性，而本研究計畫即是針對這些白蝦 的基因進行研究。首先會先確認這些基因是否與白蝦造血作用有關，接著會對確 認後的基因進行相關的功能分析，希望藉由這些研究能對白蝦甚至是甲殼類動物 的造血作用有更深入的了解。" "Hemocytes play prominent roles in crustacean innate immune system, actively participating in both the cellular and humoral defenses, such as the recognition, phagocytosis, nodulation and encapsulation of invading microbes, and the production and release of a variety of immune-related molecules. Because of their importance in crustacean immunity, it is necessary to maintain the numbers of circulating hemocytes at a relative constant level. In crustaceans, a variety of factors decreases the numbers of circulating hemocytes, such as microbial infections and environmental stresses, and hematopoiesis is the only way to replenish new circulating hemocytes. In Drosophila and mammals, a lot of genes are involved in hematopoiesis process, but so far, only a few hematopoiesis-related genes have been identified in crustacean, all of them being cloned from the freshwater crayfish Pacifactacus leniusculus. The studies in Drosophila and mammals have shown that hematopoiesis is controlled by regulators including transcription factors and components in signaling transduction pathways, and that many of them are highly conserved between Drosophila and mammals. The crustacean hematopoiesis occurs in the specific, sheet-like hematopoietic tissues (HPT), which is situated on and covers the dorsal and dorsolateral sides of the stomach. By using the next generation sequencing (NGS) strategy, we obtained the white shrimp Litopenaeus vannamei HPT and hemocyte transcriptomes, which contained 44371 and 36245 unigenes, respectively. By BLASTP analysis, we found that two dozen of Drosophila hematopoiesis regulators had matched unigenes (E value < 10-4) in our HPT and hemocyte trasncriptomes. In this project, we will focus on these unigenes to firstly determine whether they are involved in L. vannamei hematopoiesis, and then to investigate their importance and their biological functions in L. vannamei hematopoiesis. We hope that through these studies we will unveil the underlying mechanism of hematopoieisis in L. vannamei or even in crustaceans."