为探讨温度胁迫对刺参基因表达的影响，从已构建的刺参耐寒基因筛选cDNA文库中选取差异基因主要卵黄蛋白（major yolk protein，MYP）：MYP1和MYP2，利用实时荧光定量PCR研究了其在刺参胚胎发生和个体发育9个阶段（受精卵、囊胚期、原肠期、小耳状幼体、中耳幼体、大耳幼体、樽形幼体、五触手幼体和稚参）、成体7种组织（呼吸树、体腔液、肠、纵肌、体壁、雄性性腺和雌性性腺）、长时温度胁迫（20 ℃、4 ℃，30 d）和低温短时胁迫（7 ℃、4 ℃、1 ℃、-2 ℃，12 h）成体肠组织中的表达量。结果发现，MYP1和MYP2表达模式基本相同：（1）在胚胎发育阶段樽形幼体时期开始表达，随后的阶段持续表达，到稚参阶段表达量最高；（2）在7种组织中，肠中的表达量最高，在体腔液中基本不表达，其余组织中均有表达；（3）在长时（30 d）温度胁迫下，肠组织中MYP表达量由高到低依次为4 ℃、12 ℃、20 ℃，且在4 ℃的表达量为 20 ℃的6倍左右；（4）在低温短时胁迫（1 ℃、-2 ℃，12 h）条件下，肠组织中MYP表达量受到显著抑制，约为常温条件下的一半。研究表明，MYP在刺参胚胎发育的樽形幼体阶段开始合成，成体合成部位主要为肠，水温过低会抑制其表达。

In the present study,we investigated how temperature stress affected gene expressions of sea cucumber Apostichopus japonicas.Major yolk protein(MYP)gene was selected as a candidate indicator from our former pilot screening study on cold-resistant genes.Two isoforms of MYP namely,MYP1 and MYP2,were both involved,to enhance the reliability of inferences drawn by the current study.Temporal expression features of the two MYPs were surveyed for nine developmental stages(fertilized egg,blastula,gastrula,early auricularia,auricularia,late auricularia,doliolaria,pentactula,juvenile)via RT-PCR.Tissue distribution for adult A.japonicas was studied for seven tissues(respiratory tree,coelomocyte,intestine,muscle,body wall,testis,ovary).Expression profiles of the two MYPs corresponding to a long-term High/Low temperature treatment and a temporal acute cold shock treatment were investigated respectively,with intestine as the target tissue.The two MYPs presented similarities for temporal expression and tissue distribution:gradually enhanced expression from doliolarias stage to juvenile stage;and tissue-ubiquitous(but not in coelomic fluid)expression with greatest abundance in intestine.Interestingly,although the expressions of MYP presented a negative linear relationship with the constant environmental temperature(six times higher for 4 ℃ compared to 20 ℃),a sharp cold shock treatment significantly suppressed them.

国家自然科学基金项目（31072230）；国家海洋局海洋公益项目（201105016-3）；辽宁省农业攻关计划重大项目（2011203003）