講演情報
[9a-S302-8]多能性幹細胞を用いたタンパク質翻訳開始制御機構の解明
〇友田 紀一郎1,2 (1.グラッドストン研、2.京大iPS研)
キーワード：
多能性幹細胞、タンパク質翻訳開始
Our lives depend on protein expression, which is tightly regulated at multiple steps, including transcription and translation. Remarkably, some studies have revealed a poor correlation between protein and mRNA expression and that cellular protein abundance is predominantly controlled at the translation level.
Previous studies highlight the importance of translation regulation in stem cells. Pluripotent stem cells (PSCs) and adult stem cells tightly regulate global translation at low levels to maintain their stemness while increasing protein production during differentiation.
The rate-limiting step in translation is its initiation. The conventional view of translation initiation is that a single translational initiation complex, centered on eIF4G1, binds to the cap structure at the 5′ end of mRNA and scans toward the 3′ direction until it finds the start codon. Therefore, most protein translation is thought to begin this way. However, the process may be more intricate, as eIF4G1 has two homologous family members: eIF4G2 and eIF4G3. Growing evidence also suggests the widespread translation regulation by eIF4G2, although eIF4G2 does not efficiently bind to 5’ caps.
We have investigated the functions of eIF4G2 in pluripotent stem cells and identified target proteins whose protein translation appears to be controlled by eIF4G2. Inhibiting eIF4G2 function is detrimental to pluripotent stem cells, leading to differentiation and cell death. In this session, I will discuss the eIF4G2 functions in pluripotent stem cells.
Previous studies highlight the importance of translation regulation in stem cells. Pluripotent stem cells (PSCs) and adult stem cells tightly regulate global translation at low levels to maintain their stemness while increasing protein production during differentiation.
The rate-limiting step in translation is its initiation. The conventional view of translation initiation is that a single translational initiation complex, centered on eIF4G1, binds to the cap structure at the 5′ end of mRNA and scans toward the 3′ direction until it finds the start codon. Therefore, most protein translation is thought to begin this way. However, the process may be more intricate, as eIF4G1 has two homologous family members: eIF4G2 and eIF4G3. Growing evidence also suggests the widespread translation regulation by eIF4G2, although eIF4G2 does not efficiently bind to 5’ caps.
We have investigated the functions of eIF4G2 in pluripotent stem cells and identified target proteins whose protein translation appears to be controlled by eIF4G2. Inhibiting eIF4G2 function is detrimental to pluripotent stem cells, leading to differentiation and cell death. In this session, I will discuss the eIF4G2 functions in pluripotent stem cells.