The MITOCHONDRIAL TRANSCRIPT STABILITY FACTOR 4 (MTSF4) is essential for the accumulation of dicistronic rpl5-cob mRNAs in Arabidopsis thaliana.

The Arabidopsis thaliana genome harbors more than 450 nuclear genes encoding pentatricopeptide repeat (PPR) proteins that operate in the RNA metabolism of mitochondria and/or plastids. To date, the molecular function of many PPR proteins is still unknown. Here we analyzed the nucleus-encoded gene At4g19440 coding for a P-type PPR protein.