An enigma in the genetic responses of plants to salt stresses

Soil salinity is one of the main factors restricting crop production throughout the world. Various salt tolerance traits and the genes controlling these traits are responsible for coping with salinity stress in plants. These coping mechanisms include osmotic tolerance, ion exclusion, and tissue tolerance. Plants exposed to salinity stress sense the stress conditions, convey specific stimuli signals, and initiate responses against stress through the activation of tolerance mechanisms that include multiple genes and pathways. Advances in our understanding of the genetic responses of plants to salinity and their connections with yield improvement are essential for attaining sustainable agriculture. Although a wide range of studies have been conducted that demonstrate genetic variations in response to salinity stress, numerous questions need to be answered to fully understand plant tolerance to salt stress. This chapter provides an overview of previous studies on the genetic control of salinity stress in plants, including signaling, tolerance mechanisms, and the genes, pathways, and epigenetic regulators necessary for plant salinity tolerance

VvMATE1 and VvMATE2 encode putative proanthocyanidin transporters expressed during berry development in Vitis vinifera L.

Univ Talca, Inst Ciencias Biol, Talca, Chile; Perez-Diaz, R (Perez-Diaz, Ricardo); Perez-Diaz, J (Perez-Diaz, Jorge); Casaretto, JA (Casaretto, Jose A.); Gonzalez-Villanueva, E (Gonzalez-Villanueva, Enrique); Ruiz-Lara, S (Ruiz-Lara, Simon)VvMATE1 and VvMATE2 encode putative PA transporters expressed during seed development in grapevine. The subcellular localization of these MATE proteins suggests different routes for the intracellular transport of PAs. Proanthocyanidins (PAs), also called condensed tannins, protect plants against herbivores and are important quality components of many fruits. PAs biosynthesis is part of the flavonoid pathway that also produces anthocyanins and flavonols. In grape fruits, PAs are present in seeds and skin tissues. PAs are synthesized in the cytoplasm and accumulated into the vacuole and apoplast; however, little is known about the mechanisms involved in the transport of these compounds to such cellular compartments. A gene encoding a Multidrug And Toxic compound Extrusion (MATE) family protein suggested to transport anthocyanins-named VvMATE1-was used to identify a second gene of the MATE family, VvMATE2. Analysis of their deduced amino acid sequences and the phylogenetic relationship with other MATE-like proteins indicated that VvMATE1 and VvMATE2 encode putative PA transporters. Subcellular localization assays in Arabidopsis protoplasts transformed with VvMATE-GFP fusion constructs along with organelle-specific markers revealed that VvMATE1 is localized in the tonoplast whereas VvMATE2 is localized in the Golgi complex. Major expression of both genes occurs during the early stages of seed development concomitant with the accumulation of PAs. Both genes are poorly expressed in the skin of berries while VvMATE2 is also expressed in leaves. The presence of putative cis-acting elements in the promoters of VvMATE1 and VvMATE2 may explain the differential transcriptional regulation of these genes in grapevine. Altogether, these results suggest that these MATE proteins could mediate the transport and accumulation of PAs in grapevine through different routes and cellular compartments

Mating behaviour by the haddock (Melanogrammus aeglefinus)

This study examines the full repertoire of haddock reproductive behaviour, monitored in an aquarium for 3 months over each of two successive spawning seasons. Observations showed that male haddock were territorial and that visits to their territories by females triggered courtship behaviour, leading to spawning. Entry of females to the territories was induced by an acoustic and visual self-advertisement of displaying males, termed patrolling behaviour, exhibited for many hours each night for several months. The existence of sneaking behaviour by non-territorial males was observed for the first time for haddock and was supported by genetic data. Overall our observations are consistent with the behaviour expected from lekking species, as in the cod, a closely related species. Lekking is said to occur when non-resource-based aggregations of males are visited by females for the purpose of mating. Implications for the management of fish stocks are discussed

Substaging Nodal Status in Ampullary Carcinomas has Significant Prognostic Value: Proposed Revised Staging Based on an Analysis of 313 Well-Characterized Cases

BACKGROUND: Current nodal staging (N-staging) of am-pullary carcinoma in the TNM staging system distinguishes between node-negative (N0) and node-positive (N1) disease but does not consider the metastatic lymph node (LN) number. METHODS: Overall, 313 patients who underwent pancreatoduodenectomy for ampullary adenocarcinoma were categorized as N0, N1 (1–2 metastatic LNs), or N2 (≥3 metastatic LNs), as proposed by Kang et al. Clinico-pathological features and overall survival (OS) of the three groups were compared. RESULTS: The median number of LNs examined was 11, and LN metastasis was present in 142 cases (45 %). When LN-positive cases were re-classified according to the proposed staging system, 82 were N1 (26 %) and 60 were N2 (19 %). There was a significant correlation between proposed N-stage and lymphovascular invasion, perineural invasion, increased tumor size (each p < 0.001), and surgical margin positivity (p = 0.001). The median OS in LN-negative cases was significantly longer than that in LN-positive cases (107.5 vs. 32 months; p < 0.001). Patients with N1 and N2 disease had median survivals of 40 and 24.5 months, respectively (p < 0.0001). In addition, 1-, 3-, and 5-year survivals were 88, 76, 62 %, respectively, for N0; 90, 55, 31.5 %, respectively, for N1; and 68, 34, 30 %, respectively for N2 (p < 0.001). Even with multivariate modeling, the association between higher proposed N stage and shorter survival persisted (hazard ratio 1.6 for N1 and 1.9 for N2; p = 0.018). CONCLUSIONS: Classification of nodal status in ampullary carcinomas based on the number of metastatic LNs has a significant prognostic value. A revised N-staging classification system should be incorporated into the TNM staging of ampullary cancers