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Sanchez-Diaz, E.

Publications and source records attributed to Sanchez-Diaz, E..

2 recordsLinked to original sources

Functional diversity of a temperate continental flora: Wide but skewed coverage of the global spectrum of plant form and function

O_LIHabitat filtering is assumed to promote plant functional convergence, but local functional ranges are often wide. Using the Global Spectrum of Plant Form and Function (GSPFF) as global reference, we tested whether a regional flora shared the same trait trade-offs as the global flora, and whether the regional phenospace supports the habitat filtering hypothesis. C_LIO_LIWe measured six key functional traits in 268 central Argentina species. We compared this flora with the GSPFF using univariate and multivariate methods. We tested whether the regional phenospace was smaller or more skewed than expected by chance, and analysed its topography. C_LIO_LIRegional and global phenospaces shared major axes, syndromes, and trait correlations. Despite having fewer species, the regional flora broadly covered the GSPFF, but without tall, large-leaved, large-seeded trees. The most frequent species were conservative herbs and shrubs. Distinct species also showed highly conservative attributes. C_LIO_LIDespite being moderate to harsh, central Argentina environmental conditions do not appear to preclude the regional presence of most functional syndromes previously identified at the global scale. However, the regional and global floras differ in the most frequent syndromes. At the regional scale, habitat filtering shapes functional topographies more than it constrains the extent of phenospaces. C_LI

ecology↗

Exportin-mediated nucleocytoplasmic transport maintains Pch2 homeostasis during meiosis

The meiotic recombination checkpoint reinforces the order of events during meiotic prophase I, ensuring the accurate distribution of chromosomes to the gametes. The AAA+ ATPase Pch2 remodels the Hop1 axial protein enabling adequate levels of Hop1-T318 phosphorylation to support the ensuing checkpoint response. While these events are focalized at chromosome axes, the checkpoint activating function of Pch2 relies on its cytoplasmic population. In contrast, forced nuclear accumulation of Pch2 leads to checkpoint inactivation. Here, we reveal the mechanism by which Pch2 travels from the cell nucleus to the cytoplasm to maintain Pch2 cellular homeostasis. Leptomycin B treatment provokes the nuclear accumulation of Pch2, indicating that its nucleocytoplasmic transport is mediated by the Crm1 exportin recognizing proteins containing Nuclear Export Signals (NESs). Consistently, leptomycin B leads to checkpoint inactivation and impaired Hop1 axial localization. Pch2 nucleocytoplasmic traffic is independent of its association with Zip1 and Orc1. We also identify a conserved functional NES in the non-catalytic N-terminal domain of Pch2 that is required for its nucleocytoplasmic traffic and proper checkpoint activity. In sum, we unveil another layer of control of Pch2 function during meiosis involving the nuclear export via the exportin pathway that is crucial to maintain the critical balance of Pch2 distribution among different cellular compartments.

cell biology↗