背景:微藻衍生的细胞外囊泡(EV),将它们的货物转移到细胞外环境以影响受体细胞,在微藻生长和环境适应中发挥重要作用。And,它们也被认为是生物活性分子和/或人工药物分子的递送纳米载体的可持续和可再生生物资源。然而,它们的分子组成和功能仍然知之甚少。
结果:在这项研究中,隔离,表征,并对雨生红球菌衍生的EV(HpEV)进行了功能验证。结果表明,具有典型EV形态和大小的HpEV在整个生长期由雨生H.pluvialis细胞分泌,并在培养基中积累。HpEV的细胞摄取被证实。以及它们在受体细胞生长和各种生理过程中的调节作用。HpEV分泌的短期抑制导致HpEV功能性细胞成分的积累,从而在分子水平上改变这些细胞的生物反应。同时,持续抑制HpEV的分泌对生长产生负面影响,和脂肪酸和虾青素的积累。进一步进行小RNA高通量测序以深入确定HpEV中的miRNA货物和令人信服的细节。比较分析揭示了HpEV三个阶段miRNA种类和表达水平的共性和差异。总共鉴定了163个成熟的miRNA,其中一些独特的miRNA显示出最高的表达水平。HpEV的miRNA表达谱表现出明显的阶段特异性模式。此外,共鉴定了12个差异表达的miRNA,并将它们的靶基因分类为细胞周期控制,脂质运输和代谢,次生代谢产物的生物合成等。
结论:因此,有人提出HpEV的货物,包括miRNA成分,研究表明,在调节雨露嗜血杆菌细胞生理状态方面具有潜在作用。总结一下,这项工作揭示了HpEV的细胞间通讯和代谢调节功能。
BACKGROUND: Microalgae-derived extracellular vesicles (EVs), which transfer their cargos to the extracellular environment to affect recipient cells, play important roles in microalgal growth and environmental adaptation. And, they are also considered as sustainable and renewable bioresources of delivery nanocarrier for bioactive molecules and/or artificial drug molecules. However, their molecular composition and functions remain poorly understood.
RESULTS: In this study, isolation, characterization, and functional verification of Haematococcus pluvialis-derived EVs (HpEVs) were performed. The results indicated that HpEVs with typical EV morphology and size were secreted by H. pluvialis cells during the whole period of growth and accumulated in the culture medium. Cellular uptake of HpEVs by H. pluvialis was confirmed, and their roles in regulation of growth and various physiological processes of the recipient cells were also characterized. The short-term inhibition of HpEV secretion results in the accumulation of functional cellular components of HpEVs, thereby altering the biological response of these cells at the molecular level. Meanwhile, continuously inhibiting the secretion of HpEVs negatively influenced growth, and fatty acid and astaxanthin accumulation in H. pluvialis. Small RNA high-throughput sequencing was further performed to determine the miRNA cargoes and compelling details in HpEVs in depth. Comparative analysis revealed commonalities and differences in miRNA species and expression levels in three stages of HpEVs. A total of 163 mature miRNAs were identified with a few unique miRNAs reveal the highest expression levels, and miRNA expression profile of the HpEVs exhibited a clear stage-specific pattern. Moreover, a total of 12 differentially expressed miRNAs were identified and their target genes were classified to cell cycle control, lipid transport and metabolism, secondary metabolites biosynthesis and so on.
CONCLUSIONS: It was therefore proposed that cargos of HpEVs, including miRNA constituents, were suggested potential roles in modulate cell physiological state of H. pluvialis. To summarize, this work uncovers the intercellular communication and metabolism regulation functions of HpEVs.