Membrane-Potential Alteration During K+ Uptake of Different Salt-Tolerant Wheat Varieties

K＋ is the most abundant cation in plant cells and plays an important role in many ways.K＋ uptake of plant has respect to its salt resistant capacity.There are two categories of channel transportation for plants to uptake K＋,one is through K＋ channels and the other is through nonselective cation channels（NSCCs）.The transmembrane localization of K＋ may change membrane potential（MP）.In this paper,three wheat varieties with different salt tolerance were selected and the MP was measured by microelectrode during K＋ uptake.The results showed that the effects of K＋ uptake on MP through K＋ channels or NSCCs were distinct.K＋ influx through K＋ channels led to MP hyperpolarization,while K＋ influx through NSCCs resulted in depolarization.Diverse MP alteration of wheat varieties with different salt tolerance was mainly due to NSCCs-mediated K＋ uptake.Compared with the salt-tolerant wheat,the MP hyperpolarization during K＋ uptake of saltsensitive wheat was much more evident,probably because of the cation outflux through NSCCs during this process.

Neuronal Fc gamma receptor I as a novel mediator for IgG immune complex-induced peripheral sensitization

Chronic pain often accompanies immune-related diseases with an elevated level of IgG immune complex （IgG-IC） in the serum and/or the affected tissues though the underlying mechanisms are largely unknown. Fc gamma receptors （FcyRs）, known as the receptors for the Fc domain of immunoglobulin G （IgG）, are typically expressed on immune cells. A general consensus is that the activation of FcyRs by IgG-IC in such immune cells induces the release of proinflammatory cytokines from the immune cells, which may contribute to the IgG-IC-mediated peripheral sensitization. In addition to the immune cells, recent studies have revealed that FcyRI, but not FcyRII and FcyRIII, is also expressed in a subpopulation of primary sensory neurons. Moreover, IgG-IC directly excites the primary sensory neurons through neuronal FcyRI. These findings indicate that neuronal FcyRI provides a novel direct linkage between immunoglobulin and primary sensory neurons, which may be a novel target for the treatment of pain in the immune-related disorders. In this review, we summarize the expression pattern, functions, and the associated cellular signaling of FcyRs in the primary sensory neurons.

Heteromerization of TRP channel subunits: extending functional diversity

Transient receptor potential(TRP)channels are widely found throughout the animal kingdom.By serving as cellular sensors for a wide spectrum of physical and chemical stimuli,they play crucial physiological roles ranging from sensory transduction to cell cycle modulation.TRP channels are tetrameric protein complexes.While most TRP subunits can form functional homomeric channels,heteromerization of TRP channel subunits of either the same subfamily or different subfamilies has been widely observed.Heteromeric TRP channels exhibit many novel properties compared to their homomeric counterparts,indicating that co-assembly of TRP channel subunits has an important contribution to the diversity of TRP channel functions.