Disease relevance of SHO1

• In this work, we show that the Hog1 MAPK is also activated by heat stress and that Sho1, previously identified as a membrane-bound osmosensor, is required for heat stress activation of Hog1 [1].

High impact information on SHO1

• Alternatively, Pbs2p was activated by a mechanism that involves the binding of its amino terminal proline-rich motif to the Src homology 3 (SH3) domain of a putative transmembrane osmosensor Sho1p [2].
• Msb2 is localized to polarized sites on the cell surface and interacts with Cdc42 and with the osmosensor for the high osmolarity glycerol response (HOG) pathway, Sho1 [3].
• Taken together, our data suggest that Msb2 is a signaling mucin that interacts with general components, such as Cdc42 and Sho1, to promote their function in the FG pathway [3].
• We suggest that Hog1p may prevent osmolarity-induced cross talk by inhibiting Sho1p, perhaps as part of a feedback control on the HOG pathway [4].
• Protein-protein interaction affinity plays a crucial role in controlling the Sho1p-mediated signal transduction pathway in yeast [5].

Biological context of SHO1

• Defects in protein glycosylation cause SHO1-dependent activation of a STE12 signaling pathway in yeast [6].
• The use of DNA microarrays to monitor gene expression revealed that Sho1 and Msb2 regulate identical gene sets in hog1 mutants [7].
• These results suggest that Sln1p-Ssk1p and Sho1p signal transduction pathways participate in oxidative stress response [8].
• SHO1 from C. utilis, however, did complement the osmosensitivity of the sho1ssk2ssk22 strain by restoring HOG pathway function, since Hog1p dual phosphorylation after high osmotic challenge was restored in this strain after transformation with a plasmid bearing this SHO1 homologue [9].
• The Sho1 adaptor protein links oxidative stress to morphogenesis and cell wall biosynthesis in the fungal pathogen Candida albicans [10].

Anatomical context of SHO1

• One branch is dependent on the Sho1 transmembrane protein, whose primary role was found to be the binding and translocation of the Pbs2 MAPKK to the plasma membrane, and specifically to sites of polarized growth [11].
• Cdc42, but not the actin cytoskeleton, influences Sho1-dependent activation of the MAP kinase [12].
• These results reveal a role for the Sho1 protein in linking oxidative stress, cell wall biogenesis, and morphogenesis in this important human fungal pathogen [10].

Associations of SHO1 with chemical compounds

• Dimethyl sulfoxide (DMSO) treatment, which rigidifies the cell membrane, also activates the HOG pathway in both SLN1 branch- and SHO1 branch-dependent manners [13].
• Because loss of pheromone response pathway components leads to a synthetic growth defect in mannose utilization/protein glycosylation mutants, we suggest that the Sho1 --> Ste12 pathway contributes to maintenance of cell wall integrity in vegetative cells [6].

Physical interactions of SHO1

• Pbs2p requires its Pro-rich motif for binding to the Src-homology3 (SH3) domain of Sho1p, but PbsB lacks a typical Pro-rich motif [14].
• Hkr1 and Msb2 individually form a complex with Sho1, and, upon high external osmolarity stress, appear to induce Sho1 to generate an intracellular signal [15].

Regulatory relationships of SHO1

• The cell fusion defect associated with fus1Delta mutants is suppressed by a sho1Delta deletion allele, suggesting that Fus1p negatively regulates Sho1p signaling to ensure efficient cell fusion [16].

Other interactions of SHO1

• Finally, we have found that pseudohyphal growth exhibited by wild-type (HOG1) strains depends on SHO1, suggesting that Sho1p may be a receptor that feeds into the pseudohyphal growth pathway [4].
• One of these proteins, Sho1, utilizes the MAP kinase kinase kinase Ste11 to activate Pbs2 [7].
• A third osmosensing branch in Saccharomyces cerevisiae requires the Msb2 protein and functions in parallel with the Sho1 branch [7].
• The yeast high osmolarity glycerol (HOG) signaling pathway can be activated by either of the two upstream pathways, termed the SHO1 and SLN1 branches [17].
• Interestingly, these two Ste50p-SAM mutants were associated with increased activation of the mating and filamentous-growth pathways, but a reduction in the SHO1-dependent growth response to hyperosmolarity, relative to the wild-type Ste50p [18].

Analytical, diagnostic and therapeutic context of SHO1

• It also appeared from our studies that the Sho1p osmosensor is less active under severe osmotic stress conditions, whereas the Sln1p/Ypd1p/Ssk1p sensor and signal transducer functions normally under these circumstances [19].
• Sequence analysis of the newly defined SSU81 gene revealed an adjacent open reading frame (ORF) encoding a protein whose deduced amino acid sequence is identical to that of ribosomal protein L17 [20].

References