The yeast A kinases differentially regulate iron uptake and respiratory function
The yeast A kinases differentially regulate iron uptake and respiratory function
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DOI：
10.1073/pnas.100113397
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发表时间：
2000-05-23
影响因子：
11.1
通讯作者：
Fink, GR
中科院分区：
文献类型：
--
作者：
Robertson, LS;Causton, HC;Fink, GR
酵母具有三个A激酶催化亚基，其具有大于75%的同一性并且由TPK基因（TPK 1、TPK 2和TPK 3）编码[户田，T.，卡梅隆，S.，Sass，P.，Zoller，M. & Wigler，M.（1987）Cell 50，277-287]。虽然它们对于生存力是多余的，但三种A激酶对于假菌丝生长不是多余的[Robertson，L. S. & Fink，G. R.等人（1998）Proc. Acad. Sci. USA 95，13783-13787; Pan，X. & Heitman，J.（1999）Mel. Cell. 19，4874-4887];假菌丝生长需要Tpk 2，而不是Tpk 1或Tpk 3。全基因组转录谱分析揭示了三种A激酶中每一种的独特特征，从而确定了这些蛋白质之间的额外功能多样性。TPK 2负调控铁摄取相关基因，正调控海藻糖降解和水稳态相关基因。Tpk 1是支链氨基酸生物合成基因的去阻遏所必需的，这些基因似乎在维持线粒体内的铁水平和DNA稳定性方面具有第二个作用。TPK 2突变体在非发酵碳源和缺铁培养基上比野生型生长得更好的事实支持了TPK 2在呼吸生长和碳源利用中的独特作用。
Yeast has three A kinase catalytic subunits, which have greater than 75% identity and are encoded by the TPK genes (TPK1, TPK2, and TPK3) [Toda, T., Cameron, S., Sass, P., Zoller, M. & Wigler, M. (1987) Cell 50, 277-287]. Although they are redundant for viability, the three A kinases are not redundant for pseudohyphal growth [Robertson, L. S. & Fink, G. R. (1998) Proc. Natl. Acad. Sci. USA 95, 13783-13787; Pan, X. & Heitman, J. (1999) Mel. Cell. Biol. 19, 4874-4887]; Tpk2, but not Tpk1 or Tpk3, is required for pseudohyphal growth. Genome-wide transcriptional profiling has revealed unique signatures for each of the three A kinases leading to the identification of additional functional diversity among these proteins. Tpk2 negatively regulates genes involved in iron uptake and positively regulates genes involved in trehalose degradation and water homeostasis. Tpk1 is required for the derepression of branched chain amino acid biosynthesis genes that seem to have a second role in the maintenance of iron levels and DNA stability within mitochondria. The fact that TPK2 mutants grow better than wild types on nonfermentable carbon sources and on media deficient in iron supports the unique role of Tpk2 in respiratory growth and carbon source use.