Disease relevance of PAT1

• Yeast Lsm1p-7p/Pat1p deadenylation-dependent mRNA-decapping factors are required for brome mosaic virus genomic RNA translation [1].

High impact information on PAT1

• Contrastingly, overexpression of Dhh1p or Pat1p causes translational repression, P body formation, and arrests cell growth [2].
• Dhh1 is a cytoplasmic protein and is shown to be in a complex with the mRNA degradation factor Pat1/Mtr1 and with the 5'-3' exoribonuclease Xrn1 [3].
• Deletions of LSM1, 6, 7 and PAT1 genes increased the half-life of reporter mRNAs [4].
• These results indicate the involvement of a new conserved Sm-like protein complex and a new factor, Pat1p, in mRNA degradation and suggest a physical connection between decapping and exonuclease trimming [4].
• The two proteins Pat1p (Mrt1p) and Spb8p interact in vivo, are required for mRNA decay, and are functionally linked to Pab1p [5].

Biological context of PAT1

• PAT1 is not an essential gene, but its deletion leads to a thermosensitive phenotype [5].
• Here, we have studied the effects of deleting the PAT1 gene on chromosomal stability, with particular reference to rates of homologous recombination within the rDNA locus [6].
• Previously, we have shown that pat1 delta mutants exhibit a slow-growth phenotype and an elevated frequency of both mitotic and meiotic chromosome mis-segregation [6].
• However, pat1 delta strains display additional manifestations of more general genomic instability, in that they show mild sensitivity to UV light and an increased incidence of interchromosomal recombination between heteroalleles [6].
• We show that pat1 delta strains mimic top2 mutants in displaying an elevated rate of intrachromosomal excision recombination at the rDNA locus, but not elsewhere in the genome [6].

Anatomical context of PAT1

• The PAT1 gene is not essential for viability, although disruption of the gene severely impairs translation initiation in vivo, resulting in the accumulation of 80S ribosomes and in a large decrease in the amounts of heavier polysomes [7].
• These findings indicate that the PAT1 gene is necessary for accurate chromosome transmission during cell division in eukaryotic cells and suggest that the interaction of Pat1p and topoisomerase II is an important component of this function [8].
• Pat1p contributes to the efficiency of translation in a yeast cell-free system [7].
• High-resolution sucrose density gradient analysis showed that, while mutating factors in the Lsm1p-7p/Pat1p complex completely inhibited viral RNA translation, the levels of viral RNA associated with ribosomes were only slightly reduced in mutant yeast [1].

Associations of PAT1 with chemical compounds

• We report the isolation of the PAT1 gene (for protein associated with topoisomerase II), which encodes a novel 90 kDa proline- and glutamine-rich protein that interacts with a highly conserved, leucine-rich region of topoisomerase II in vivo [8].
• A fraction of Pat1p cosediments with free 40S ribosomal subunits on sucrose gradients [7].
• This mutation inactivated the ability of PAT1 to complement the defective n-decane utilization of the disruptant [9].

Regulatory relationships of PAT1

• Deletion of the PAT1 gene affects translation initiation and suppresses a PAB1 gene deletion in yeast [7].

Other interactions of PAT1

• Further analysis has shown that PAT1 is allelic with mrt1-3, a mutation previously reported to affect decapping and to bypass suppress pab1Delta, as is also the case for dcp1, spb8, and mrt3 [5].
• These results indicate that PAT1 encodes peroxisomal acetoacetyl-CoA thiolase and is essential for n-decane utilization in Y. lipolytica [9].

Analytical, diagnostic and therapeutic context of PAT1

• Finally, yeast two-hybrid assays and co-immunoprecipitation studies of human cell extracts identified PAT1 as a protein that interacts with R3 [10].

References