UBA6

    UBA6（Ubiquitin-like modifier-activating enzyme 6）是人体中由UBA6基因编码的一种蛋白质。UBA6蛋白通过将ATP与其C端的甘氨酸残基腺苷化，然后将这个残基连接到E1中半胱氨酸的侧链上，形成一个泛素-E1巯基酯和游离的AMP（腺苷二磷酸）。UBA6专一于泛素，不激活类似泛素的肽链。与UBE1在底物E2充电特异性上有所不同，不会充电细胞周期E2，如CDC34。UBA6对胚胎发育至关重要。它还参与UBD/FAT10的结合过程。UBA6的第二剪切异构体可能在泛素系统中起关键作用，影响精子发生和男性生育能力。

    Ubiquitin-like modifier-activating enzyme 6 is a protein in humans that is encoded by UBA6 gene. Activates ubiquitin by first adenylating its C-terminal glycine residue with ATP, and thereafter linking this residue to the side chain of a cysteine residue in E1, yielding a ubiquitin-E1 thioester and free AMP. Specific for ubiquitin, does not activate ubiquitin-like peptides. Differs from UBE1 in its specificity for substrate E2 charging. Does not charge cell cycle E2s, such as CDC34. Essential for embryonic development. Required for UBD/FAT10 conjugation. Isoform 2 may play a key role in ubiquitin system and may influence spermatogenesis and male fertility.