title: Liaison alcaline: Pals entice non-endosomal ESCRTs to  the plasma membrane for pH signaling.
abstract: The alkaline pH-responsive Pal/Rim signal transduction pathway mediating regulation of gene expression by ambient pH has been extensively studied in Aspergillus nidulans and Saccharomyces cerevisiae. In A. nidulans, PalH, PalI, PalF, PalC, PalA and PalB are required for the proteolytic activation of the executing transcription factor PacC. Although necessary, Pal proteins are insufficient to transmit the signal, which additionally requires ESCRT-I, II and Vps20 with Snf7 in ESCRT-III. Although this initially suggested cooperation between a plasma membrane sensor and an ESCRT-containing Pal complex on endosomes, recent evidence convincingly indicates that pH signaling actually takes place in plasma membrane-associated foci in which Pal proteins and an ESCRT-III polymer scaffold cooperate for pH signaling purposes, representing another non-endosomal role of ESCRT components.
authors.affiliation: Department of Cellular and Molecular Biology, Centro de Investigaciones Biológicas CSIC, Ramiro de Maeztu 9, Madrid 28040, Spain. penalva@cib.csic.es
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Peñalva
authors.forename: Daniel
authors.initials: D
authors.lastname: Lucena-Agell
authors.forename: Herbert N
authors.initials: HN
authors.lastname: Arst
mesh_terms: D001233:Aspergillus nidulans / Q000235:genetics / Q000378:metabolism; D002154:Calpain / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism*; D056827:Endosomal Sorting Complexes Required for Transport / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D055503:Protein Multimerization; D059748:Proteolysis; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D056827:Endosomal Sorting Complexes Required for Transport; D005656:Fungal Proteins; D002154:Calpain; C117906:Capn7 protein, human