Disease relevance of SPT20

• In this report we described the cloning and characterization of ADA5, a gene identified by resistance to GAL4-VP16-mediated toxicity [1].

High impact information on SPT20

• We have studied the in vivo role of two other SAGA components, Spt3 and Spt20, at the well-characterized GAL1 promoter [2].
• Gene induction in response to unfolded protein in the endoplasmic reticulum is mediated through Ire1p kinase interaction with a transcriptional coactivator complex containing Ada5p [3].
• In addition, partial SAGA complexes containing Spt7 can be assembled in the absence of both Spt20 and Ada1 [4].
• Further, ADA5 cofractionates and coprecipitates with ADA3 [1].
• Most interestingly, ADA5 is identical to SPT20 (S.M. Roberts and F. Winston, Mol. Cell. Biol. 16: 3206-3213, 1996), showing that it shares phenotypes with the ADA and SPT family of genes [1].

Biological context of SPT20

• Consistent with its having an important function in transcription in vivo, SPT20 was also recently identified as ADA5 and has been shown to be important for transcriptional activation (G.A. Marcus, J [5].

Other interactions of SPT20

• Systematic analysis has demonstrated that spt20 delta/ada5 delta and spt7 delta mutations cause lethality with every snf/swi and srb/mediator mutation tested [6].
• Our results demonstrate that Spt3 and Spt20 are required for full delta promoter activity, but that Gcn5, another member of SAGA, is not required [7].
• The transcriptional co-activator ADA5 is required for HAC1 mRNA processing in vivo [8].
• Interestingly, the spt3, spt8, and spt20 mutants behaved differently than other Spt-Ada-Gcn5-acetyltransferase (SAGA) mutants [9].

References