Fig 8

Fig 8 Model of the consequences of Ctu1 deficiency in zebrafish, figured by Figdraw.

Recently, the essential role of mcm⁵s²U₃₄ tRNA modification and their modifying enzymes in proliferation and development has been demonstrated from yeast to mammals [7]. For example, double deletion of the partner enzymes (Ctu1 and Elp3) is lethal to the cell in yeast [14]. Inactivation of the CTU complex leads to a thermosensitive decrease with aberrant development in the nematode and fission yeast [15]. In mice, a deficiency in Elp1 causes male infertility [52], while Elp3-KO embryos exhibits significant growth retardation and fails to develop beyond E12.5 [13]. Here our finding provides the first experimental evidence that s²U₃₄ tRNA modifying enzyme CTU1 is essential in cellular proliferation and development in vertebrates.