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Competing Interests: Declaration of Competing Interest None.

Different microclimates can have significant impact on the physiology of succulents that inhabit arid environments such as the Mojave Desert (California). We investigated variation in leaf physiology, morphology and anatomy of two dominant Mojave Desert monocots, Yucca brevifolia (Joshua tree) and Hesperoyucca whipplei , growing along a soil water availability gradient. Stomatal conductance ( g s ) and leaf thickness were recorded in the field at three different sites (north-western slope, south-eastern slope, and alluvial fan) in March of 2019. We sampled leaves from three individuals per site per species and measured in the lab relative water content at the time of g s measurements, saturated water content, cuticular conductance, leaf morphological traits (leaf area and length, leaf mass per area, % loss of thickness in the field and in dried leaves), and leaf venation. We found species varied in their g s : while Y. brevifolia showed significantly higher g s in the alluvial fan than in the slopes, H. whipplei was highest in the south-eastern slope. The differences in g s did not relate to differences in leaf water content, but rather to variation in number of veins per mm 2 in H. whipplei and leaf width in Y. brevifolia . Our results indicate that H. whipplei displays a higher water conservation strategy than Y. brevifolia . We discuss these differences and trends with water availability in relation to species' plasticity in morphology and anatomy and the ecological consequences of differences in 3-dimensional venation architecture in these two species., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Jolly, Zailaa, Farah, Woojuh, Libifani, Arzate, Caranto, Correa, Cuba, Calderon, Garcia, Gastelum, Gutierrez, Haro, Orozco, Pinlac, Miranda, Nava, Nguyen, Pedroza, Perdomo, Pezzini, Yuen and Scoffoni.)

Enterovirus 71 (EV71) induces apoptosis to promote viral particle release. Earlier work showed that EV71 utilizes its 3C protease to induce apoptosis in a caspase-3-dependent pathway, though the mechanism is unknown. However, work from Vagner, Holcik and colleagues showed that host protein heterogeneous ribonucleoprotein A1 (hnRNP A1) binds the IRES of cellular apoptotic peptidase activating factor 1 (apaf-1) mRNA to repress its translation. In this work, we show that apaf-1 expression is essential for EV71-induced apoptosis. EV71 infection or ectopic expression of 3C protease cleaves hnRNP A1, which abolishes its binding to the apaf-1 IRES. This allows IRES-dependent synthesis of apaf-1, activation of caspase-3, and apoptosis. Thus, we reveal a novel mechanism that EV71 utilizes for virus release via a 3C protease-hnRNP A1-apaf-1-caspase-3-apoptosis axis., Competing Interests: The authors have declared that no competing interests exist.