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Rubus huagaoxiensis and R. lingtianus , two new species of Rosaceae from Sichuan, Southwest China, are described and illustrated. Rubus huagaoxiensis is morphologically similar to R. setchuenensis , but differs from the latter by gray tomentose branchlets, thicker leaves which are usually adaxially pubescent, larger and subflabellate stipules, 0.3–0.5 cm long pedicels, sepals which are triangular to ovate and abaxially densely gray tomentose-villous, white petals which are abaxially and adaxially villous along midrib, villous styles, and spheroidal pollen grains. Rubus lingtianus is morphologically similar to R. setchuenensis and R. huagaoxiensis , but differs from R. setchuenensis by having leathery leaves, acute lobes of leaf blade, larger and subflabellate stipules, broadly ovate sepals with acute or obtuse apex, white flowers, red fruits, and subprolate pollen grains with verrucate-striate-perforate ornamentation. Rubus lingtianus differs from R. huagaoxiensis by having leathery leaves, mature leaf blade which is adaxially glabrous or soft-hairy along veins only, usually glabrous petals, styles base with few soft hairs, red fruits, and subprolate pollen grains with verrucate-striate-perforate ornamentation. Morphological comparison among these three species is given.

The mitochondrion is essential for energy metabolism and production of reactive oxygen species (ROS). In intact cells, respiratory mitochondria exhibit spontaneous "superoxide flashes", the quantal ROS-producing events consequential to transient mitochondrial permeability transition (tMPT). Here we perform the first in vivo imaging of mitochondrial superoxide flashes and tMPT activity in living mice expressing the superoxide biosensor mt-cpYFP, and demonstrate their coupling to whole-body glucose metabolism. Robust tMPT/superoxide flash activity occurred in skeletal muscle and sciatic nerve of anesthetized transgenic mice. In skeletal muscle, imaging tMPT/superoxide flashes revealed labyrinthine three-dimensional networks of mitochondria that operate synchronously. The tMPT/superoxide flash activity surged in response to systemic glucose challenge or insulin stimulation, in an apparently frequency-modulated manner and involving also a shift in the gating mode of tMPT. Thus, in vivo imaging of tMPT-dependent mitochondrial ROS signals and the discovery of the metabolism-tMPT-superoxide flash coupling mark important technological and conceptual advances for the study of mitochondrial function and ROS signaling in health and disease.

In dividing embryos, a localized elevation in intracellular Ca2+ ([Ca2+]i) at the cleavage furrow has been shown to be essential for cytokinesis. However, the underlying mechanisms for generating and maintaining these [Ca2+]i gradients throughout cytokinesis are not fully understood. In the present study, we analyzed the role of inositol 1,4,5-trisphosphate receptors (IP3Rs) and endoplasmic reticulum (ER) distribution in determining the intracellular Ca2+ gradients in early zebrafish blastomeres. Application of the injected Ca2+ indicator, Indo-1, showed that during the first cell division a standing Ca2+ gradient was formed ∼35 min after fertilization, with the [Ca2+]i spatially decaying from 500–600 nmol/L at the cleavage furrow to 100–200 nmol/L around the nucleus. While the IP3R immunohistochemical fluorescence was relatively concentrated in the peri-furrow region, ER labeling was relatively enriched in both peri-furrow and peri-nuclear regions. Numeric simulation suggested that a divergence in the spatial distribution of IP3R and the locations of Ca2+ uptake within the ER was essential for the formation of a standing Ca2+ gradient, and the Ca2+ gradient could only be well-established under an optimal stoichiometry of Ca2+ uptake and release. Indeed, while inhibition of IP3R Ca2+ release blocked the generation of the Ca2+ gradient at a lower [Ca2+]i level, both Ca2+ release stimulation by inositol 1,4,5-trisphosphate (IP3) injection and ER Ca2+ pump inhibition by cyclopiazonic acid also eliminated the Ca2+ gradients at higher [Ca2+]i levels. Our results suggest a dynamic relationship between ER-mediated Ca2+ release and uptake that underlies the maintenance of the perifurrow Ca2+ gradient and is essential for cytokinesis of zebrafish embryos.