Stanford Advisors


All Publications


  • Two auxins are better than one: BiAux joins forces with auxin to enhance lateral root formation. Plant physiology Torres-Martinez, H. H. 2024

    View details for DOI 10.1093/plphys/kiae132

    View details for PubMedID 38445801

  • The primary root procambium contributes to lateral root formation through its impact on xylem connection. Current biology : CB Blanco-Tourinan, N., Torres-Martinez, H. H., Augstein, F., Champeyroux, C., von der Mark, C., Carlsbecker, A., Dubrovsky, J. G., Rodriguez-Villalon, A. 2023

    Abstract

    The postembryonic formation of lateral roots (LRs) starts in internal root tissue, the pericycle. An important question of LR development is how the connection of the primary root vasculature with that of the emerging LR is established and whether the pericycle and/or other cell types direct this process. Here, using clonal analysis and time-lapse experiments, we show that both the procambium and pericycle of the primary root (PR) affect the LR vascular connectivity in a coordinated manner. We show that during LR formation, procambial derivates switch their identity and become precursors of xylem cells. These cells, together with the pericycle-origin xylem, participate in the formation of what we call a "xylem bridge" (XB), which establishes the xylem connection between the PR and the nascent LR. If the parental protoxylem cell fails to differentiate, XB is still sometimes formed but via a connection with metaxylem cells, highlighting that this process has some plasticity. Using mutant analyses, we show that the early specification of XB cells is determined by CLASS III HOMEODOMAIN-LEUCINE ZIPPER (HD-ZIP III) transcription factors (TFs). Subsequent XB cell differentiation is marked by the deposition of secondary cell walls (SCWs) in spiral and reticulate/scalariform patterns, which is dependent on the VASCULAR-RELATED NAC-DOMAIN (VND) TFs. XB elements were also observed in Solanum lycopersicum, suggesting that this mechanism may be more widely conserved in plants. Together, our results suggest that plants maintain vascular procambium activity, which safeguards the functionality of newly established lateral organs by assuring the continuity of the xylem strands throughout the root system.

    View details for DOI 10.1016/j.cub.2023.03.061

    View details for PubMedID 37071995

  • Extending resolution within a single imaging frame NATURE COMMUNICATIONS Torres-Garcia, E., Pinto-Camara, R., Linares, A., Martinez, D., Abonza, V., Brito-Alarcon, E., Calcines-Cruz, C., Valdes-Galindo, G., Torres, D., Jablonski, M., Torres-Martinez, H. H., Martinez, J. L., Hernandez, H. O., Ocelotl-Oviedo, J. P., Garces, Y., Barchi, M., D'Antuono, R., Boskovic, A., Dubrovsky, J. G., Darszon, A., Buffone, M. G., Rodriguez Morales, R., Manuel Rendon-Mancha, J., Wood, C. D., Hernandez-Garcia, A., Krapf, D., Crevenna, A. H., Guerrero, A. 2022; 13 (1): 7452

    Abstract

    The resolution of fluorescence microscopy images is limited by the physical properties of light. In the last decade, numerous super-resolution microscopy (SRM) approaches have been proposed to deal with such hindrance. Here we present Mean-Shift Super Resolution (MSSR), a new SRM algorithm based on the Mean Shift theory, which extends spatial resolution of single fluorescence images beyond the diffraction limit of light. MSSR works on low and high fluorophore densities, is not limited by the architecture of the optical setup and is applicable to single images as well as temporal series. The theoretical limit of spatial resolution, based on optimized real-world imaging conditions and analysis of temporal image stacks, has been measured to be 40 nm. Furthermore, MSSR has denoising capabilities that outperform other SRM approaches. Along with its wide accessibility, MSSR is a powerful, flexible, and generic tool for multidimensional and live cell imaging applications.

    View details for DOI 10.1038/s41467-022-34693-9

    View details for Web of Science ID 000934495300023

    View details for PubMedID 36460648

    View details for PubMedCentralID PMC9718789

  • A mutation in THREONINE SYNTHASE 1 uncouples proliferation and transition domains of the root apical meristem: experimental evidence and in silico proposed mechanism DEVELOPMENT Garcia-Gomez, M. L., Reyes-Hernandez, B. J., Sahoo, D. P., Napsucialy-Mendivil, S., Quintana-Armas, A. X., Pedroza-Garcia, J. A., Shishkova, S., Torres-Martinez, H. H., Pacheco-Escobedo, M. A., Dubrovsky, J. G. 2022; 149 (21)

    Abstract

    A continuum from stem to transit-amplifying to a differentiated cell state is a common theme in multicellular organisms. In the plant root apical meristem (RAM), transit-amplifying cells are organized into two domains: cells from the proliferation domain (PD) are displaced to the transition domain (TD), suggesting that both domains are necessarily coupled. Here, we show that in the Arabidopsis thaliana mto2-2 mutant, in which threonine (Thr) synthesis is affected, the RAM lacks the PD. Through a combination of cell length profile analysis, mathematical modeling and molecular markers, we establish that the PD and TD can be uncoupled. Remarkably, although the RAM of mto2-2 is represented solely by the TD, the known factors of RAM maintenance and auxin signaling are expressed in the mutant. Mathematical modeling predicts that the stem cell niche depends on Thr metabolism and that, when disturbed, the normal continuum of cell states becomes aborted.

    View details for DOI 10.1242/dev.200899

    View details for Web of Science ID 000903918600001

    View details for PubMedID 36278862

    View details for PubMedCentralID PMC9796171