The signal peptide sequence is known to increase transport efficiency to organelles in eukaryotic cells. In this study, we focus on the signal peptide of the vacuolar protein for vacuolar targeting. The signal peptide sequence QRPL of carboxypeptidase Y (CPY) was inserted inside the interest protein that does not locate in the vacuole for vacuolar targeting. We constructed recombinant strains MBTL-Q-DJ1 and MBTL-Q-DJ2 containing QRPL and green florescent protein (GFP) or aldehyde dehydrogenase 6 (ALD6), respectively. The protein location was then confirmed by confocal microscopy. Fascinatingly, the green fluorescent protein that contains QRPL inside the sequence could be expressed faster than its natural form (within 1 h after induction). Also, the aldehyde removal activity of ALD6 protein in the recombinant yeast was then analyzed by measuring the luminescent intensity in Vibrio fischeri. We confirmed that MBTL-Q-DJ2 containing ALD6 protein has the aldehydes-reducing ability, and in particular, the highest efficiency showed at 500 μg/μL of vacuolar enzyme. In summary, the signal peptide QRPL could be used not only to transport proteins accurately to vacuole but also to improve the protein activity and shorten the induction time.

已知信号肽序列可提高向真核细胞中的细胞器的转运效率。在这项研究中，我们专注于用于液泡靶向的液泡蛋白的信号肽。羧肽酶 Y (CPY) 的信号肽序列 QRPL 被插入到不在液泡中的目的蛋白内，用于液泡靶向。我们构建了分别含有 QRPL 和绿色荧光蛋白 (GFP) 或醛脱氢酶 6 (ALD6) 的重组菌株 MBTL-Q-DJ1 和 MBTL-Q-DJ2。然后通过共聚焦显微镜确认蛋白质位置。令人着迷的是，在序列中包含 QRPL 的绿色荧光蛋白的表达速度可以比其自然形式更快（诱导后 1 小时内）。还有，费氏弧菌。我们证实了含有 ALD6 蛋白的 MBTL-Q-DJ2 具有还原醛的能力，特别是在 500 μg/μL 的液泡酶时表现出最高的效率。综上所述，信号肽QRPL不仅可以将蛋白质准确转运到液泡中，还可以提高蛋白质活性，缩短诱导时间。