Puromycin-sensitive aminopeptidase (PSA) belongs to the M1 zinc metallopeptidase family. PSA is the most abundant aminopeptidase in the brain and plays a role in the metabolism of neuropeptides including those involved in neurodegeneration. A cDNA DjPsa was identified from the planarian Dugesia japonica cDNA library. It contains a 639-bp open reading frame corresponding to a deduced protein of 212 amino acids. Whole mount in situ hybridization revealed that DjPsa is expressed in the brain and ventral nerve cords of intact and regenerating animals and demonstrates a tissue and stage-specific expression pattern of DjPsa in developing embryos and larvae. Knocking down DjPsa gene expression with RNA interference during planarian regeneration inhibits the brain reformation completely. The results suggest that DjPsa is required for planarian brain regeneration.

中文翻译：

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嘌呤霉素敏感的氨基肽酶DjPsa的平面同源物是大脑再生所必需的。

嘌呤霉素敏感性氨基肽酶（PSA）属于M1锌金属肽酶家族。PSA是脑中最丰富的氨基肽酶，并且在包括神经变性在内的神经肽的代谢中发挥作用。cDNA DjPsa是从涡虫日本粳稻cDNA文库中鉴定的。它包含一个639 bp的开放阅读框，对应于212个氨基酸的推导蛋白。整个安装的原位杂交揭示了DjPsa在完整和再生动物的大脑和腹侧神经索中表达，并证明了DjPsa在发育中的胚胎和幼虫中的组织和阶段特异性表达模式。击倒DjPsa涡虫再生过程中带有RNA干扰的基因表达完全抑制了大脑的重建。结果表明，DjPsa是涡虫脑再生所必需的。