KIF3A and KIF3B are homologous motor subunits of the Kinesin II protein family. KIF3A, KIF3B, and KAP3 form a heterotrimeric complex and play a significant role in spermatogenesis. Here, we first cloned full-length kif3a/3b cDNAs from Larimichthys polyactis. Lp-kif3a/3b are highly related to their homologs in other animals. The proteins are composed of three domains, an N-terminal head domain, a central stalk domain, and a C-terminus tail domain. Lp-kif3a/3b mRNAs were found to be ubiquitously expressed in the examined tissues, with high expression in the testis. Fluorescence in situ hybridization (FISH) was used to analyze the expression of Lp-kif3a/3b mRNAs during spermiogenesis. The results showed that Lp-kif3a/3b mRNAs had similar expression pattern and were continuously expressed during spermiogenesis. From middle spermatid to mature sperm, Lp-kif3a/3b mRNAs gradually localized to the side of the spermatid where the midpiece and tail form. In addition, we used immunofluorescence (IF) to observe that Lp-KIF3A protein co-localizes with tubulin during spermiogenesis. In early spermatid, Lp-KIF3A protein and microtubule signals were randomly distributed in the cytoplasm. In middle spermatid, however, the protein was detected primarily around the nucleus. In late spermatid, the protein migrated primarily to one side of the nucleus where the tail forms. In mature sperm, Lp-KIF3A and microtubules accumulated in the midpiece. Moreover, Lp-KIF3A co-localized with the mitochondria. In mature sperm, Lp-KIF3A and mitochondria were present in the midpiece. Therefore, Lp-KIF3A/KIF3B may be involved in spermiogenesis in L. polyactis, particularly during nuclear reshaping and tail formation.

中文翻译：

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KIF3A / 3B的表达和潜在功能，以促进多毛线虫精子发生过程中的核重塑和尾巴形成。

KIF3A和KIF3B是Kinesin II蛋白家族的同源运动亚基。KIF3A，KIF3B和KAP3形成异三聚体复合物，在精子发生中起重要作用。在这里，我们首先从多头猴（Larimichthys polyactis）克隆了全长kif3a / 3b cDNA 。Lp - kif3a / 3b与它们在其他动物中的同系物高度相关。蛋白质由三个结构域组成，一个N末端的头部结构域，一个中央茎结构域和一个C末端的尾部结构域。发现Lp - kif3a / 3b mRNA在受检组织中普遍表达，在睾丸中高表达。荧光原位杂交（FISH）用于分析Lp的表达-精子发生过程中的kif3a / 3b mRNAs。结果表明，Lp - kif3a / 3b mRNA具有相似的表达模式，并在精子发生过程中持续表达。从中型精子到成熟精子，Lp - kif3a / 3b mRNA逐渐定位于中段和尾部形成的精子一侧。此外，我们使用免疫荧光（IF）观察到Lp -KIF3A蛋白在精子发生过程中与微管蛋白共定位。在早期精子细胞，脂蛋白-KIF3A蛋白和微管信号随机分布在细胞质中。然而，在中型精子细胞中，主要在细胞核周围检测到该蛋白质。在精子晚期，蛋白质主要迁移到尾巴形成的细胞核一侧。在成熟精子中，Lp -KIF3A和微管积聚在中段。此外，Lp -KIF3A与线粒体共定位。在成熟的精子中，Lp -KIF3A和线粒体存在于中段。因此，L-对KIF3A / KIF3B可能参与在精子形成L.黄鱼，特别是在核整形和尾部形成。