Department of Biology, Loyola University Chicago, Chicago, Illinois, United States of America.
Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Chicago, Illinois, United States of America.
PLoS One. 2024 Oct 31;19(10):e0306676. doi: 10.1371/journal.pone.0306676. eCollection 2024.
Phosducin-like proteins (PhLP) are thioredoxin domain-containing proteins that are highly conserved across unicellular and multicellular organisms. PhLP family proteins are hypothesized to function as co-chaperones in the folding of cytoskeletal proteins. Here, we present the initial molecular, biochemical, and functional characterization of CG4511 as Drosophila melanogaster PhLP3. We cloned the gene into a bacterial expression vector and produced enzymatically active recombinant PhLP3, which showed similar kinetics to previously characterized orthologues. A fly strain homozygous for a P-element insertion in the 5' UTR of the PhLP3 gene exhibited significant downregulation of PhLP3 expression. We found these male flies to be sterile. Microscopic analysis revealed altered testes morphology and impairment of spermiogenesis, leading to a lack of mature sperm. Among the most significant observations was the lack of actin cones during sperm maturation. Excision of the P-element insertion in PhLP3 restored male fertility, spermiogenesis, and seminal vesicle size. Given the high level of conservation of PhLP3, our data suggests PhLP3 may be an important regulator of sperm development across species.
Phosducin 样蛋白（PhLP）是一种含硫氧还蛋白结构域的蛋白，在单细胞和多细胞生物中高度保守。PhLP 家族蛋白被假设为细胞骨架蛋白折叠的共伴侣。在这里，我们首次对果蝇 PhLP3 的 CG4511 进行了分子、生化和功能表征。我们将该基因克隆到细菌表达载体中，并产生了具有酶活性的重组 PhLP3，其动力学与先前表征的同源物相似。在 PhLP3 基因 5'UTR 处带有 P 元件插入的果蝇纯合子表现出 PhLP3 表达的显著下调。我们发现这些雄性果蝇不育。显微镜分析显示睾丸形态改变和精子发生受损，导致成熟精子缺乏。最显著的观察结果之一是在精子成熟过程中缺乏肌动蛋白锥体。切除 PhLP3 中的 P 元件插入可恢复雄性生育力、精子发生和精囊大小。鉴于 PhLP3 的高度保守性，我们的数据表明 PhLP3 可能是跨物种精子发育的重要调节剂。
