Late Cenozoic diversification of the austral genus <i>Lagenophora</i> (Astereae, Asteraceae)

Lagenophora (Astereae, Asteraceae) has 14 species in New Zealand, Australia, Asia, southern South America, Gough Island and Tristan da Cunha. Phylogenetic relationships in Lagenophora were inferred using nuclear and plastid DNA regions. Reconstruction of spatio-temporal evolution was estimated using parsimony, Bayesian inference and likelihood methods, a Bayesian relaxed molecular clock and ancestral area and habitat reconstructions. Our results support a narrow taxonomic concept of Lagenophora including only a core group of species with one clade diversifying in New Zealand and another in South America. The split between the New Zealand and South American Lagenophora dates from 11.2Mya [6.1-17.4 95% highest posterior density (HPD)]. The inferred ancestral habitats were openings in beech forest and subalpine tussockland. The biogeographical analyses infer a complex ancestral area for Lagenophora involving New Zealand and southern South America. Thus, the estimated divergence times and biogeographical reconstructions provide circumstantial evidence that Antarctica may have served as a corridor for migration until the expansion of the continental ice during the late Cenozoic. The extant distribution of Lagenophora reflects a complex history that could also have involved direct long-distance dispersal across southern oceans.Facultad de Ciencias Naturales y MuseoInstituto de Limnología "Dr. Raúl A. Ringuelet

Late Cenozoic diversification of the austral genus <i>Lagenophora</i> (Astereae, Asteraceae)

Lagenophora (Astereae, Asteraceae) has 14 species in New Zealand, Australia, Asia, southern South America, Gough Island and Tristan da Cunha. Phylogenetic relationships in Lagenophora were inferred using nuclear and plastid DNA regions. Reconstruction of spatio-temporal evolution was estimated using parsimony, Bayesian inference and likelihood methods, a Bayesian relaxed molecular clock and ancestral area and habitat reconstructions. Our results support a narrow taxonomic concept of Lagenophora including only a core group of species with one clade diversifying in New Zealand and another in South America. The split between the New Zealand and South American Lagenophora dates from 11.2Mya [6.1-17.4 95% highest posterior density (HPD)]. The inferred ancestral habitats were openings in beech forest and subalpine tussockland. The biogeographical analyses infer a complex ancestral area for Lagenophora involving New Zealand and southern South America. Thus, the estimated divergence times and biogeographical reconstructions provide circumstantial evidence that Antarctica may have served as a corridor for migration until the expansion of the continental ice during the late Cenozoic. The extant distribution of Lagenophora reflects a complex history that could also have involved direct long-distance dispersal across southern oceans.Facultad de Ciencias Naturales y MuseoInstituto de Limnología "Dr. Raúl A. Ringuelet

Broad targeting of resistance to apoptosis in cancer

Apoptosis or programmed cell death is natural way of removing aged cells from the body. Most of the anti-cancer therapies trigger apoptosis induction and related cell death networks to eliminate malignant cells. However, in cancer, de-regulated apoptotic signaling, particularly the activation of an anti-apoptotic systems, allows cancer cells to escape this program leading to uncontrolled proliferation resulting in tumor survival, therapeutic resistance and recurrence of cancer. This resistance is a complicated phenomenon that emanates from the interactions of various molecules and signaling pathways. In this comprehensive review we discuss the various factors contributing to apoptosis resistance in cancers. The key resistance targets that are discussed include (1) Bcl-2 and Mcl-1 proteins; (2) autophagy processes; (3) necrosis and necroptosis; (4) heat shock protein signaling; (5) the proteasome pathway; (6) epigenetic mechanisms; and (7) aberrant nuclear export signaling. The shortcomings of current therapeutic modalities are highlighted and a broad spectrum strategy using approaches including (a) gossypol; (b) epigallocatechin-3-gallate; (c) UMI-77 (d) triptolide and (e) selinexor that can be used to overcome cell death resistance is presented. This review provides a roadmap for the design of successful anti-cancer strategies that overcome resistance to apoptosis for better therapeutic outcome in patients with cancer

The sugar beet gene encoding the sodium/proton exchanger 1 (BvNHX1) is regulated by a MYB transcription factor

Sodium/proton exchangers (NHX) are key players in the plant response to salinity and have a central role in establishing ion homeostasis. NHXs can be localized in the tonoplast or plasma membranes, where they exchange sodium ions for protons, resulting in sodium ions being removed from the cytosol into the vacuole or extracellular space. The expression of most plant NHX genes is modulated by exposure of the organisms to salt stress or water stress. We explored the regulation of the vacuolar NHX1 gene from the salt-tolerant sugar beet plant (BvNHX1) using Arabidopsis plants transformed with an array of constructs of BvHNX1::GUS, and the expression patterns were characterized using histological and quantitative assays. The 5′ UTR of BvNHX1, including its intron, does not modulate the activity of the promoter. Serial deletions show that a 337 bp promoter fragment sufficed for driving activity that indistinguishable from that of the full-length (2,464 bp) promoter. Mutating four putative cis-acting elements within the 337 bp promoter fragment revealed that MYB transcription factor(s) are involved in the activation of the expression of BvNHX1 upon exposure to salt and water stresses. Gel mobility shift assay confirmed that the WT but not the mutated MYB binding site is bound by nuclear protein extracted from salt-stressed Betavulgaris leaves

Authors, copyright and open access: Making it work for you

Exploring traditional publication options, and what choices can be made by researchers

F. S. Bennett and others

"Spr. F.S.Bennett. 6 AAT.Coy RAE. SX29091 1942. . . . . . . . . . R.Doc.Caust 6AAT Coy RAE (Dec) . . . . . . . . . C.Spang.Barkla 6AAT.Coy RAE. (Dec) Kadina."Sapper F. S. Bennett. 6 Australian Army Transport Company, Royal Australian Engineers. SX29091 1942. . . . . . . . . . R. Doc. Caust 6 Australian Army Transport Company, Royal Australian Engineers (Deceased). . . . . . . . . . C. Spang. Barkla 6 Australian Army Transport Company, Royal Australian Engineers. (Deceased) Kadina