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SUMMARY: Plant cell walls are essential for defining plant growth and development, providing structural support to the main body and responding to abiotic and biotic cues. Cellulose, the main structural polymer of plant cell walls, is synthesized at the plasma membrane by cellulose synthase complexes (CSCs). The construction and transport of CSCs to and from the plasma membrane is poorly understood but is known to rely on the coordinated activity of cellulose synthase‐interactive protein 1 (CSI1), a key regulator of CSC trafficking. In this study, we found that Trs85, a TRAPPIII complex subunit, interacted with CSI1 in vitro. Using functional genetics and live‐cell imaging, we have shown that trs85‐1 mutants have reduced cellulose content, stimulated CSC delivery, an increased population of static CSCs and deficient clathrin‐mediated endocytosis in the primary cell wall. Overall, our findings suggest that Trs85 has a dual role in the trafficking of CSCs, by negatively regulating the exocytosis and clathrin‐mediated endocytosis of CSCs. Significance Statement: The synthesis of cellulose requires the transportation of cellulose synthase complexes (CSCs) to and from the plasma membrane. Our study has identified that Trs85, a TRAPPIII subunit, is important in both the delivery and endocytosis of CSCs at the plasma membrane in Arabidopsis. [ABSTRACT FROM AUTHOR]

SUMMARY: Confocal microscopy has greatly aided our understanding of the major cellular processes and trafficking pathways responsible for plant growth and development. However, a drawback of these studies is that they often rely on the manual analysis of a vast number of images, which is time‐consuming, error‐prone, and subject to bias. To overcome these limitations, we developed Dot Scanner, a Python program for analyzing the densities, lifetimes, and displacements of fluorescently tagged particles in an unbiased, automated, and efficient manner. Dot Scanner was validated by performing side‐by‐side analysis in Fiji‐ImageJ of particles involved in cellulose biosynthesis. We found that the particle densities and lifetimes were comparable in both Dot Scanner and Fiji‐ImageJ, verifying the accuracy of Dot Scanner. Dot Scanner largely outperforms Fiji‐ImageJ, since it suffers far less selection bias when calculating particle lifetimes and is much more efficient at distinguishing between weak signals and background signal caused by bleaching. Not only does Dot Scanner obtain much more robust results, but it is a highly efficient program, since it automates much of the analyses, shortening workflow durations from weeks to minutes. This free and accessible program will be a highly advantageous tool for analyzing live‐cell imaging in plants. Significance Statement: Live‐cell imaging analyses of fluorescently tagged particles in biological systems often require significant manual input that is time‐consuming and subject to bias. We have developed a free Python program, Dot Scanner, to allow users without any programming experience to analyze large datasets rapidly, efficiently, and with reduced bias. [ABSTRACT FROM AUTHOR]

Abstract: Though grandparents hope to influence the new generation, to pass on their values, understanding, wisdom, and faith, little empirical evidence exists that reveals if (or how) grandparents actually influence [...]

Two views on women in ministry (Rev. ed.). Edited by James R. Beck. Grand Rapids, MI: Zondervan. 2005. 344 pp. $16.99. paper. James R. Beck, the editor of this volume [...]

September 11 in History: A Watershed Moment? edited by Mary L. Dudziak. American Encounters/Global Interactions series. Durham, North Carolina and London, Duke University Press, 2003. 240 pp. $79.95 US (cloth), […]