RESUMO
CBL-interacting protein kinases (CIPKs) mediate many plant responses to abiotic stress. However, their functions are poorly understood in halophytes. In this study, we isolated a CIPK gene, NtCIPK2, from the halophyte Nitraria tangutorum. By sequence alignment and the construction of a phylogenetic tree, we found that NtCIPK2 is similar to CIPK2 proteins from other plants, and contains conserved domains and motifs. The promoter of NtCIPK2 harbors many cis-acting elements that might be recognized and bound by transcription factors that are related to hormones and stress responses. NtCIPK2 was ubiquitously and robustly expressed in all tested organs, and was induced by salinity, drought, heat, and cold stress. The overexpression of NtCIPK2 in Escherichia coli caused better growth against high salinity, alkalinity, and osmotic conditions, dehydration, and extreme temperatures (i.e., heat and cold) compared to the control. Thus, NtCIPK2 is a candidate gene that might improve the stress tolerance of crops and herbs through genetic manipulation.
Assuntos
Regulação da Expressão Gênica de Plantas , Magnoliaceae/genética , Proteínas de Plantas/genética , Proteínas Serina-Treonina Quinases/genética , Plantas Tolerantes a Sal/genética , Sequência de Aminoácidos , Arabidopsis/enzimologia , Arabidopsis/genética , Clonagem Molecular , Temperatura Baixa , Secas , Escherichia coli/genética , Escherichia coli/metabolismo , Temperatura Alta , Magnoliaceae/classificação , Magnoliaceae/enzimologia , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tolerância ao Sal , Plantas Tolerantes a Sal/enzimologia , Alinhamento de Sequência , Estresse FisiológicoRESUMO
PREMISE OF THE STUDY: The family Magnoliaceae s.l. is a basal angiosperm family with two subfamilies-Magnolioideae and Liriodendroideae, which differ by the types and structure of their fruits and seeds. The late Albian genus Archaeanthus shares many features of its reproductive organs with Magnoliaceae s.l., but its pericarp anatomy was never studied in detail. A broad-scale carpological investigation of Archaeanthus and Magnoliaceae s.l. was undertaken to reveal the nature of the similarities in fruit structure and to reconstruct Archaeanthus pericarp anatomy. These data are important to determine the early stages of fruit morphogenesis and thus to clarify relationships of Archaeanthus to the taxa of Magnoliaceae s.l. METHODS: The pericarp anatomy was studied with light microscopy, SEM, and polarizing microscopy. KEY RESULTS: The dehiscent, polyspermous follicles shed from the receptacle of Archaeanthus share similarities with dehiscent follicles of Magnoliaceae s.s. and shedding nutlets of Liriodendron. The seeds of Archaeanthus are dorsiventrally flattened, ovoid, and encircled with a single circular wing. The pericarps of all the taxa studied are differentiated into exocarp (epidermis), multilayered mesocarp, and endocarp (fiber-like sclereids). The mesocarp consists of parenchyma with scattered secretory cells and sclereid clusters (Magnoliaceae s.s., Archaeanthus) or composed by sclerenchyma (Liriodendron). CONCLUSIONS: The specializations of dehiscent multifollicles of unknown Cretaceous ancestors for different modes of seed and fruitlet dispersal formed the basis for the differentiation of two evolutionary lines with their divergence occurring more than 100 million years ago: Magnoliaceae s.s. and the Archaeanthus-Liriodendroidea-Liriodendron line (Liriodendraceae s.l.) within the order Magnoliales.
Assuntos
Frutas/anatomia & histologia , Magnoliaceae/anatomia & histologia , Magnoliopsida/anatomia & histologia , Análise por Conglomerados , Frutas/classificação , Frutas/ultraestrutura , Magnoliaceae/classificação , Magnoliaceae/ultraestrutura , Magnoliopsida/classificação , Magnoliopsida/ultraestrutura , Folhas de Planta/anatomia & histologia , Folhas de Planta/classificação , Folhas de Planta/ultraestrutura , Brotos de Planta/anatomia & histologia , Brotos de Planta/classificação , Brotos de Planta/ultraestrutura , Sementes/anatomia & histologia , Sementes/classificação , Sementes/ultraestruturaRESUMO
A new species, Manglietia pubipedunculata Q. W. Zeng & X. M. Hu (Magnoliaceae) is described and illustrated from Yunnan, China. In addition to macromorphological examination, we comparatively studied on micromorphology of leaf epidermis, leaf structure, and epidermal cell on the sclerotesta. This new species is similar to M. kwangtungensis in terms of having dense pubescence, however, their pubescence are quite different. Manglietia pubipedunculata has appressed, compressed, shorter and sparser pubescence consisting of single or two cells. Moreover, it differs from M. kwangtungensis by showing shorter and thicker peduncles, longer styles, basal carpels covered with sparsely brown appressed pubescence, and more ovules per carpel. Furthermore, the new species has thinner leaves, brown and rugged surfaces on sclerotesta, and the alveolate cell pattern consisting of pentagon or hexagon cells with papilla on secondary cell wall under the observation by SEM. The phylogenetic analysis from two nuclear PHYA and LEAFY and chloroplast trnH-psbA sequences of 11 taxa reveals that M. pubipedunculata is a distinct species.
Assuntos
DNA de Plantas/genética , Magnoliaceae/anatomia & histologia , Magnoliaceae/classificação , China , Magnoliaceae/genética , Filogenia , Componentes Aéreos da Planta/anatomia & histologia , Componentes Aéreos da Planta/genética , Epiderme Vegetal/ultraestrutura , Análise de Sequência de DNA/métodosRESUMO
The early diverged Magnoliaceae shows a historical temperate-tropical distribution among lineages indicating divergent evolution, yet which ecophysiological traits are phylogenetically conserved, and whether these traits are involved in correlated evolution remain unclear. Integrating phylogeny and 20 ecophysiological traits of 27 species, from the four largest sections of Magnoliaceae, we tested the phylogenetic signals of these traits and the correlated evolution between trait pairs. Phylogenetic niche conservatism (PNC) in water-conducting and nutrient-use related traits was identified, and correlated evolution of several key functional traits was demonstrated. Among the three evergreen sections of tropical origin, Gwillimia had the lowest hydraulic-photosynthetic capacity and the highest drought tolerance compared with Manglietia and Michelia. Contrastingly, the temperate centred deciduous section, Yulania, showed high rates of hydraulic conductivity and photosynthesis at the cost of drought tolerance. This study elucidated the regulation of hydraulic and photosynthetic processes in the temperate-tropical adaptations for Magnoliaceae species, which led to strong phylogenetic signals and PNC in ecophysiological traits across divergent lineages of Magnoliaceae.
Assuntos
Magnoliaceae/classificação , Filogenia , Ecossistema , Magnoliaceae/fisiologia , Análise de Componente PrincipalRESUMO
Total genomic DNA samples of Chinese traditional medicine(CTM) Cortex Magnoliae Officinalis ("Houpo"), its counterfeits and substitutes were amplified by DNA amplification fingerprinting(DAF). Their amplified DNA banding patterns were distinguished on PAGE. The results show that DAF can be used to identify CTM "Houpo", its counterfeits and substitutes, which is also quite valuable for correctly introducing original plant.