High impact information on SED1

• Genetic analysis showed that the mutant phenotype is due to the interaction between two mutations, a cold-sensitive mutation gcs1 and a suppressor mutation sed1 [1].
• Analysis of genes affected in transcription revealed that SED1 and SRL1 in particular are required to reconstruct cell wall stability in the absence of multiple GPI-anchored mannoproteins [2].
• Deletion of SED1 causes a 3.5-fold increase in the rate of mitochondrial DNA point mutations as well as a 4.3-fold increase in the rate of loss of respiration [3].
• Deletion of the sed1 gene results in a reduction in the quantity of Mip1p and also affects the levels of a mitochondrially-expressed protein, Cox3p [3].
• Our results point towards a role for Sed1p in mitochondrial genome maintenance [3].

Biological context of SED1

• Ectopic expression of SED1 rescues both the aberrant growth phenotype and the translation defect of grc5-1(ts) temperature-sensitive cells [4].
• To elucidate the roles of genes involved in the cell wall biogenesis and function in Saccharomyces cerevisiae, we isolated and characterized mutants that were lethal in a strain in which the SED1 gene encoding a cell wall mannoprotein was disrupted [5].
• Amino acid sequence analysis revealed that this protein is the product of the SED1 gene [6].
• The Al tests indicated that the HSP150 protein served a basal protective role in Al stress, but SED1 did not; both of the genes had protective roles for oxidative stresses [7].
• Subsequently, we analysed the effects of the shut-off of SED1 in a sed1 and mnn9 double mutant: cells after the shut-off showed anomalous cellular morphology and died in the mitotic M phase [5].

Anatomical context of SED1

• SED1 was formerly identified as a multicopy suppressor of erd2, which encodes a protein involved in retrieval of luminal endoplasmic reticulum proteins from the secretory pathway [6].
• Furthermore, we report that Sed1p associates with translating ribosomes suggesting a novel, cytoplasmic role for Sed1p [4].
• Indirect immunofluorescence analysis of Sed1p localization shows that Sed1p is targeted to the mitochondria [3].

Associations of SED1 with chemical compounds

• Depletion of the cell-wall mannoprotein Sed1p provided resistance to lactic acid, although the expression of SED1 was induced by exposure to lactic acid [8].
• Protective roles of two aluminum (Al)-induced genes, HSP150 and SED1 of Saccharomyces cerevisiae, in Al and oxidative stresses [7].
• Sed1p is very rich in threonine and serine and, like other structural cell wall proteins, contains a putative signal sequence for the addition of a glycosylphosphatidylinositol anchor [6].
• The SED1 gene (YDR077W), coding for the major cell wall glycoprotein of Saccharomyces cerevisiae stationary-phase cells, contains two blocks of tandem repeat units located within two distinct regions of the nucleotide sequence [9].
• However, the mannoprotein Sed1p and the glucan synthase Fks2p were also crucial for cell-wall stability in mutant scw4scw10 [10].

Physical interactions of SED1

• Translational regulator RpL10p/Grc5p interacts physically and functionally with Sed1p, a dynamic component of the yeast cell surface [4].
• This occurred despite the lack of an Aft1p-binding consensus region on the upstream region of SED1 or a high concentration of free iron [11].

Other interactions of SED1

• Successful incorporation of HA-tagged Sed1p into the cell wall involves KRE6 [12].
• The highest proportion of cell wall incorporation was achieved with Cwp2p, Ag alpha 1p, or Sed1p as an anchor [13].
• The cell wall bound forms of fusion proteins consisting of the anchor regions of Sed1p or Flo1p and alpha-galactosidase were also recognized by an anti beta-1,6-glucan antiserum [14].

Analytical, diagnostic and therapeutic context of SED1

• The segregation analyses of the SED1 length variants and other genetic markers in 13 isolates representative of each PCR profile suggested that molecular mechanisms involved in minisatellite expansion and contraction may be responsible for SED1 heterozygosities within a population of homothallic must isolates of S. cerevisiae [9].
• To confirm the physical interaction between the Sed1p C-terminal fragment and the hydrophilic N-terminal fragment of Arn3p, we used an in vitro co-immunoprecipitation assay and a growth test of the strain with bait and SED1 plasmids in quadruple amino acid-depleted medium [11].

References