Abstract：
:Protein kinases AKT and PKBR1 of Dictyostelium belong to the AGC protein kinase superfamily. AKT and PKBR1 are phosphorylated at similar sites by phosphoinositide-dependent kinase 1 (PDK1) and TORC2 kinases; however, they have different subcellular localizing domains. AKT has a phosphoinositide 3-kinase (PI3K)/phosphatidylinositol (3,4,5)-trisphosphate [PtdIns(3,4,5)P(3)]-regulated PH (pleckstrin homology) domain whereas PKBR1 is myristoylated and persistently membrane localized. Using strains defective for PI3K/PtdIns(3,4,5)P(3)-, PDK1- and TORC2-signaling or strains that express phospho-site mutants of AKT and PKBR1, we dissect the different roles of PI3K/PtdIns(3,4,5)P(3), PDK1 and TORC2. We show that activation of AKT and PKBR1 requires PDK1-site phosphorylation, but that phosphorylation by TORC2 is insufficient for AKT or PKBR1 activation. However, PDK1-site phosphorylation is dependent on phosphorylation by TORC2, which suggests that there is regulatory coordination among PDK1, TORC2 and their phospho-site targets. This defines a separate input for signaling in control of chemotaxis and dependency on PDK1 function. We also demonstrate that PDK1 in Dictyostelium functions independently of PI3K/PtdIns(3,4,5)P(3). Finally, we show that AKT and PKBR1 exhibit substrate selectivity and identify two novel lipid-interacting proteins preferentially phosphorylated by AKT. Despite certain similarities, AKT and PKBR1 have distinct regulatory paths that impact activation and effector targeting, with PDK1 serving a central role.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Liao XH,Buggey J,Kimmel ARdoi
10.1242/jcs.064022subject
Has Abstractpub_date
2010-03-15 00:00:00pages
983-92issue
Pt 6eissn
0021-9533issn
1477-9137pii
123/6/983journal_volume
123pub_type
杂志文章abstract：:The oligosaccharyltransferase (OST) complex catalyses the N-glycosylation of polypeptides entering the endoplasmic reticulum, a process essential for the productive folding and trafficking of many secretory and membrane proteins. In eukaryotes, the OST typically comprises a homologous catalytic STT3 subunit complexed ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.094599
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abstract：:Skeletal and heart muscle-specific variant of the α subunit of nascent polypeptide associated complex (skNAC; encoded by NACA) is exclusively found in striated muscle cells. Its function, however, is largely unknown. Previous reports have demonstrated that skNAC binds to m-Bop/Smyd1, a multi-functional protein that re...
journal_title：Journal of cell science
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journal_title：Journal of cell science
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journal_title：Journal of cell science
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journal_title：Journal of cell science
pub_type： 杂志文章,评审
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journal_title：Journal of cell science
pub_type： 杂志文章
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更新日期：2016-01-01 00:00:00
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pub_type： 杂志文章
doi：10.1242/jcs.188060
更新日期：2017-01-01 00:00:00
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journal_title：Journal of cell science
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doi：
更新日期：2001-02-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1978-10-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1995-01-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.002717
更新日期：2007-03-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1981-02-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.054551
更新日期：2009-12-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1990-10-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.129668
更新日期：2013-12-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1997-08-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.02795
更新日期：2006-03-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1985-08-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.114231
更新日期：2013-01-15 00:00:00
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pub_type： 杂志文章
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更新日期：2019-11-08 00:00:00
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pub_type： 杂志文章
doi：
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doi：
更新日期：1998-06-01 00:00:00
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pub_type： 杂志文章
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journal_title：Journal of cell science
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doi：
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pub_type： 杂志文章,评审
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更新日期：2012-03-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1980-04-01 00:00:00
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journal_title：Journal of cell science
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更新日期：2011-10-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1997-04-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1995-11-01 00:00:00
