High impact information on SPR1

• These observations suggest that SPR1 is involved in microtubule polymerization dynamics and/or guidance, which in turn influences touch-induced directional cell expansion and axial twisting [1].
• Characterization of the mutant phenotypes suggested that SPR1 may control anisotropic cell expansion through MT-dependent processes [2].
• We propose that a microtubule-dependent process and SPR1/SPR2 act antagonistically to control directional cell elongation by preventing elongating cells from potential twisting [3].
• Expression analyses revealed that SPR1 and SP1L genes are transcribed in partially overlapping tissues [4].
• These observations suggest that SPR1 and SP1Ls act redundantly in maintaining the cortical MT organization essential for anisotropic cell growth, and that the helical growth phenotype of spr1 results from a partially compromised state of cortical MTs [4].

Biological context of SPR1

• The spr1spr2 double mutant's phenotype is synergistic, suggesting that SPR1 and SPR2 act on a similar process but in separate pathways in controlling cell elongation [3].

Associations of SPR1 with chemical compounds

• The touch-dependent sku6 root skewing phenotype is suppressed by the antimicrotubule drugs propyzamide and oryzalin, and right skewing is exacerbated by cold treatment [1].
• Root expansion studies also showed that the botero and spiral1 mutants were hypersensitive to latrunculin B [5].

Regulatory relationships of SPR1

• The effects of sos1 in suppressing spiral1 defects and in causing abnormal drug responses were nullified in the presence of the hkt1 Na(+) influx carrier mutation in roots but not in hypocotyls [6].

Other interactions of SPR1

• These results suggest that cytoplasmic salt imbalance caused by insufficient SOS1 activity compromises cortical microtubule functions in which microtubule-localized SPIRAL1 is specifically involved [6].
• Microtubule organization is partly disrupted in the spiral1 mutant of Arabidopsis thaliana, which displays a right-handed helical growth phenotype in rapidly elongating epidermal cells [6].

References