Search

Cyclic nucleotide-gated channels (CNGCs) are non-selective cation channels localized on the plasmalemma, which are involved in the growth and development as well as the regulatory mechanism in adversity of a plant. In this study, a total of 143 CNGC genes in legumes were identified and divided into four groups according to the grouping method of Arabidopsis thaliana for evolutionary analysis. According to the phylogenetic relationship with CNGCs in Arabidopsis thaliana, we assigned the names for all individual CNGC members. The CNGC genes in soybean are localized on chromosomes with a relatively random distribution. And all CNGC genes show similar conserved motifs and gene structures, especially the closer the homology, the higher the similarity. The identification of cis-elements well illustrates the key role of CNGC genes in adversity stress. The functional verification results of disease stress showed that four GmCNGCs were specifically expressed in the plasmalemma position during the stress process, and through functional enrichment, it was found that the mode of its participation and coordination is to regulate the concentration of inorganic ions inside and outside the membrane through the transmembrane ion channel. In this paper, CNGC family genes in soybean were identified, and those involved in disease stress were screened combined with physiological stress response and omics analysis, preliminarily revealing the basic laws of CNGCs involved in the disease and stress resistance of soybean, and providing important gene resources and theoretical reference for resistance breeding of soybean.

The antennal sensilla of alate Myzus persicae were mapped using transmission electron microscopy and the ultrastructure of sensilla trichoidea, coeloconica, and placoidea are described. Trichoid sensilla, located on the tip of the antennae, are innervated by 2–4 neurons, with some outer dendrites reaching the distal end of the hair. Coeloconic sensilla in primary rhinaria are of two morphological types, both equipped with two dendrites. Dendrites of Type II coeloconic sensilla are enveloped in the dendrite sheath, containing the sensillum lymph. In sensilla coeloconica of Type I, instead, dendrites are enclosed by an electron opaque solid cuticle, with no space left for the sensillum lymph. The ultrastructure of big placoid sensillum reveals the presence of three groups of neurons, with 2–3 dendrites in each neuron group, while both small placoid sensilla are equipped with a single group of neurons, consisting of three dendrites. Both large and small placoid sensilla bear multiple pores on the outer cuticle. The function of these sensilla is also discussed. J. Morphol. 276:219–227, 2015. © 2014 Wiley Periodicals, Inc.

The morphology and distribution of the antennal sensilla of adult diving beetle Cybister japonicus Sharp (Dytiscidae, Coleoptera), have been examined. Five types of sensilla on the antennae were identified by scanning electron microscope (SEM) and transmission electron microscope (TEM). Sensilla placodea and elongated s. placodea are the most abundant types of sensilla, distributing only on the flagellum. Both these types of sensilla carry multiple pore systems with a typical function as chemoreceptors. Three types of s. coeloconica (Type I-III) were also identified, with the characterization of the pit-in-pit style, and carrying pegs externally different from each other. Our data indicated that both type I and type II of s. coleconica contain two bipolar neurons, while the type III of s. coleconica contains three dendrites in the peg. Two sensory dendrites in the former two sensilla are tightly embedded inside the dendrite sheath, with no space left for sensilla lymph. There are no specific morphological differences in the antennal sensilla observed between males and females, except that the males have longer antennae and more sensilla than the females.

Odorant binding proteins (OBPs) play critical roles in chemical communication of insects, as they recognize and transport environmental chemical signals to receptors. The diving beetle Cybister japonicus Sharp shows a remarkable sexual dimorphism. The foreleg tarsi of males are equipped with large suction cups, believed to help holding the female during underwater courtship and mating. Here, we identified two OBPs highly and specifically expressed in male tarsi, suggesting important functions of these structures in chemical communication. The first protein, CjapOBP1, exhibits the 6 conserved cysteines motif of classic OBPs, while the second, CjapOBP2, contains only four cysteines and can be assigned to the sub-class of C-minus OBPs. Both proteins were expressed in a bacterial system and the purified recombinant proteins were used to for antibodies preparation. Western Blot analysis showed that CjapOBP1 is predominantly expressed in male tarsi and could be also detected in antennae and palpi of both sexes, while CjapOBP2, besides male tarsi, is also present in testis. Ligand-binding experiments showed a good binding affinity between CjapOBP1, CjapOBP2 and citral and coniferyl aldehyde, respectively. These results support a possible function of these two OBPs in the male foreleg tarsi of diving beetles in chemical communication.

The antennal sensilla of Myzus persicae were mapped using scanning and transmission electron microscopy. Placoid sensilla and coeloconic sensilla were found on the 6th segments, whereas 2 types of trichoid sensilla were present all through the length of the antenna. A single sensillum placoideum was located on the 5th segment, whereas alate aphids also presented placoid sensilla on the 3rd antennal segment. Immunocytochemical localization of odorant-binding proteins (OBPs) was performed on ultrathin sections of antennal chemosensilla. The antiserum against OBP7 intensively labeled all placoid sensilla from both primary and secondary rhinaria, with gold granules concentrated in the lymph surrounding the dendrite. OBP6 and OBP3 could also be detected in placoid sensilla, but less strongly than OBP7. Barely significant reaction or no reaction was observed with antibodies against OBP8.

Chemosensory proteins (CSPs) are small soluble proteins often associated with chemosensory organs in insects but include members involved in other functions, such as pheromone delivery and development. Although the CSPs of the sensory organs have been extensively studied, little is known on their functions in other parts of the body. A first screening of the available databases has identified 70 sequences encoding CSPs in the oriental locust Locusta migratoria manilensis. Applying proteomic analysis, we have identified 17 of them abundantly expressed in the female reproductive organs, but only one (CSP91) in male organs. Bacterially expressed CSP91 binds fatty acids with a specificity for oleic and linoleic acid, as well as medium-length alcohols and esters. The same acids have been detected as the main gas chromatographic peaks in the dichloromethane extracts of reproductive organs of both sexes. The abundance and the number of CSPs in female reproductive organs indicates important roles for these proteins. We cannot exclude that different functions can be associated with each of the 17 CSPs, including delivery of semiochemicals, solubilization of hormones, direct control of development, or other unknown tasks.

Silver staining is widely used to detect protein in polyacrylamide gels when high sensitivity is required. A simple and rapid protocol for silver staining of proteins following PAGE was developed in the present study. The number of steps was reduced compared to conventional protocol by combining fixing, rinsing, and soaking into a single impregnating step, thus achieving detection of proteins in 20 min. The present method is as sensitive as current protocols with the advantage of saving time and costs.