High impact information on RPT4

• Here, we demonstrate that proteasomal ATPases Rpt4 and Rpt6 function to connect these two histone modifications [1].
• Consistent with their role in H3 methylation, we also find that mutations in Rpt4 and 6-but not components of the 20S proteasome-disrupt telomeric gene silencing [1].
• Additionally, we have shown localization of a functional Pcs1-green fluorescent protein fusion to the nucleus throughout the cell cycle [2].
• The Gal4 activation domain binds Sug2 protein, a proteasome component, in vivo and in vitro [3].
• Additionally, we describe a genetic interaction between RPT4 and the naturally polymorphic gene SSD1, which in wild-type form modifies the rpt4-145 phenotype such that cells arrest in G2 of the first cycle with complete bipolar spindles [4].

Biological context of RPT4

• Surprisingly, Csm1's homolog in Schizosaccharomyces pombe, Pcs1, is essential for accurate chromosome segregation during mitosis and meiosis II [5].

Other interactions of RPT4

• Sug1 and Sug2 are two of six ATPases in the 19S regulatory particle of the 26S proteasome [6].
• The role of Rpn4p to function as a transregulator in yeast is corroborated by its ability of stimulating proteasome-associated control element-driven lacZ expression and by experiments using the RPT4 and RPT6 gene promoters coupled to the bacterial cat gene as a reporter [7].

Analytical, diagnostic and therapeutic context of RPT4

• Evolutionary relationships based on sequence analysis show that both CADp44 and yeast Sug2p are distinct from the other five CAD ATPases found in the PA700, and together comprise the sixth and newest CAD subunit of the regulatory complex of the 26S proteasome [8].

References