Abstract：
Under nitrogen deficient conditions, the Aurantiochytrium limacinum strain BL10 greatly increases the production of docosahexaenoic acid (DHA) and n-6 docosapentaenoic acid. Researchers have yet to elucidate the mechanism by which BL10 promotes the activity of polyunsaturated fatty acid synthase (Pfa), which plays a key role in the synthesis of polyunsaturated fatty acid (PUFA). Analysis in the current study revealed that in nitrogen-depleted environments, BL10 boosts the transcription and synthesis of proteins by facilitating the expression of pfa genes via transcriptional regulation. It was also determined that BL10 adjusts the lengths of the 5\'- and 3\'-untranslated regions (suggesting post-transcriptional regulation) and modifies the ratio of two Pfa1 isoforms to favor PUFA production via post-translational regulation (ubiquitination). These findings clarify the exceptional DHA production of BL10 and provide additional insights into the regulatory mechanisms of PUFA biosynthesis in Aurantiochytrium.
摘要：
在缺氮条件下，该菌株BL10极大地增加了二十二碳六烯酸(DHA)和n-6二十二碳五烯酸的产量。研究人员尚未阐明BL10促进多不饱和脂肪酸合酶（Pfa）活性的机制，在多不饱和脂肪酸(PUFA)的合成中起着关键作用。当前研究中的分析表明，在贫氮环境中，BL10通过转录调节促进pfa基因的表达来促进蛋白质的转录和合成。还确定BL10调整了5'和3'非翻译区的长度（提示转录后调节），并修改了两个Pfa1同工型的比例，以通过翻译后调节（泛素化）促进PUFA的产生。这些发现阐明了BL10的特殊DHA产生，并提供了对金曲中PUFA生物合成调节机制的更多见解。
