Cotton(Gossypium spp.),a major global fiber crop,serves as an ideal model for research on plant cell development.According to the acid growth theory,plasma membrane(PM)H+-ATPase(HA)regulates cell wall acidification,th...Cotton(Gossypium spp.),a major global fiber crop,serves as an ideal model for research on plant cell development.According to the acid growth theory,plasma membrane(PM)H+-ATPase(HA)regulates cell wall acidification,thereby promoting cell elongation and providing a mechanistic framework for understanding this process.However,its application to cotton fiber cells has remained limited.In this study,the acid growth theory was utilized to investigate the elongation of cotton fibers.Comparative genomics revealed an expansion in the number of gene family members associated with acid growth,including PM HA and transmembrane kinase(TMK)genes,in tetraploid cotton.Transcriptomic analysis highlighted the co-expression of these genes during fiber elongation.Functional validation using chemical modulators and CRISPR-Cas9-mediated knockout mutants demonstrated that PM HA activity is essential for apoplastic acidification and fiber elongation.Specifically,GhHA4A and GhTMK3A were identified as potential regulators of proton extrusion;their loss-of-function mutants exhibited elevated apoplastic pH and reduced fiber length.Furthermore,the results indicated that an optimal apoplastic pH is required for fiber elongation,whereas insufficient or excessive acidification inhibits growth.Spatiotemporal modulation of PM HA activity in transgenic cotton plants enhanced fiber length without affecting other fiber-and seed-related traits,demonstrating the potential of the acid growth theory for fiber improvement.These findings not only extend the acid growth theory beyond conventional model systems but also provide an innovative strategy for increasing fiber length in cotton breeding.展开更多
The ever-increasing atmospheric CO_(2) concentration is a key driver of modern global warming.However,the low heat capacity of atmosphere and strong convection processes in the troposphere both limit heat retention.Gi...The ever-increasing atmospheric CO_(2) concentration is a key driver of modern global warming.However,the low heat capacity of atmosphere and strong convection processes in the troposphere both limit heat retention.Given the higher heat capacity and CO_(2) concentration in soil compared to the atmosphere,the direct contributions of soil to the greenhouse effect may be significant.By experimentally manipulating CO_(2) concentrations both in the soil and the atmosphere,we demonstrated that the soil-retained heat and the slower soil heat transmission decrease the amount of heat energy leaking from the earth.Furthermore,the soil air temperature was affected by soil CO_(2) concentration,with the highest value recorded at 7500 ppm CO_(2).This study indicates that soil and soil CO_(2),together with atmospheric CO_(2),play a crucial role in the greenhouse effect.The spatial and temporal heterogeneity of soils and soil CO_(2) should be further investigated,given their potentially significant influence on global climate change.展开更多
基金supported by the National Key R&D Program of China(2024YFD1200305)the Henan Province Graduate Joint Training Base Project(YJS2024JD26)the Henan Kaifeng Cotton Science and Tech-nology Backyard.
文摘Cotton(Gossypium spp.),a major global fiber crop,serves as an ideal model for research on plant cell development.According to the acid growth theory,plasma membrane(PM)H+-ATPase(HA)regulates cell wall acidification,thereby promoting cell elongation and providing a mechanistic framework for understanding this process.However,its application to cotton fiber cells has remained limited.In this study,the acid growth theory was utilized to investigate the elongation of cotton fibers.Comparative genomics revealed an expansion in the number of gene family members associated with acid growth,including PM HA and transmembrane kinase(TMK)genes,in tetraploid cotton.Transcriptomic analysis highlighted the co-expression of these genes during fiber elongation.Functional validation using chemical modulators and CRISPR-Cas9-mediated knockout mutants demonstrated that PM HA activity is essential for apoplastic acidification and fiber elongation.Specifically,GhHA4A and GhTMK3A were identified as potential regulators of proton extrusion;their loss-of-function mutants exhibited elevated apoplastic pH and reduced fiber length.Furthermore,the results indicated that an optimal apoplastic pH is required for fiber elongation,whereas insufficient or excessive acidification inhibits growth.Spatiotemporal modulation of PM HA activity in transgenic cotton plants enhanced fiber length without affecting other fiber-and seed-related traits,demonstrating the potential of the acid growth theory for fiber improvement.These findings not only extend the acid growth theory beyond conventional model systems but also provide an innovative strategy for increasing fiber length in cotton breeding.
基金supported by the National Natural Science Foundation of China(41877054,31570516)the Zhongyuan Scholar Program(182101510005)the CAS/SAFEA International Partnership Program for Creative Research Teams.
文摘The ever-increasing atmospheric CO_(2) concentration is a key driver of modern global warming.However,the low heat capacity of atmosphere and strong convection processes in the troposphere both limit heat retention.Given the higher heat capacity and CO_(2) concentration in soil compared to the atmosphere,the direct contributions of soil to the greenhouse effect may be significant.By experimentally manipulating CO_(2) concentrations both in the soil and the atmosphere,we demonstrated that the soil-retained heat and the slower soil heat transmission decrease the amount of heat energy leaking from the earth.Furthermore,the soil air temperature was affected by soil CO_(2) concentration,with the highest value recorded at 7500 ppm CO_(2).This study indicates that soil and soil CO_(2),together with atmospheric CO_(2),play a crucial role in the greenhouse effect.The spatial and temporal heterogeneity of soils and soil CO_(2) should be further investigated,given their potentially significant influence on global climate change.
