Palaeoethnobotanical analysis of plant remains discovered in the graveyard of the Haihun Marquis,Nanchang, China

Vegetation History and Archaeobotany - Analysis of plant remains of 73 taxa obtained from the graveyard of the Haihun Marquis (circa 59 bc) at Nanchang, China, is presented. Chronology was...     

HSP90s are required for NLR immune receptor accumulation in Arabidopsis

Heat shock proteins (HSPs) serve as molecular chaperones for diverse client proteins in many biological processes. In plant immunity, cytosolic HSP90s participate in the assembly, stability control and/or activation of immune receptor complexes. In this paper we report that in addition to the well‐established positive roles that HSP90 isoforms play in plant immunity, they are also involved in the negative regulation of immune receptor accumulation. Point mutations in two HSP90 genes, HSP90.2 and HSP90.3, were identified from a forward genetic screen designed to isolate mutants with enhanced disease resistance. We found that specific mutations in HSP90.2 and HSP90.3 lead to heightened accumulation of immune receptors, including SNC1, RPS2 and RPS4. HSP90s may assist SGT1 in the formation of SCF E3 ubiquitin ligase complexes that target immune receptors for degradation. Such regulation is critical for maintaining appropriate levels of immune receptor proteins to avoid autoimmunity.     

A Comparison of Hypoglycemic Activity of Three Species of Basidiomycetes Rich in Vanadium

The hypoglycemic activity of fermented mushroom of three fungi of basidiomycetes rich in vanadium was studied in this paper. Alloxan- and adrenalin-induced hyperglycemic mice were used in the study. The blood glucose and the sugar tolerance were determined. After the mice were administered (ig) with Coprinus comatus rich in vanadium, the blood glucose of alloxan-induced hyperglycemic mice decreased (p < 0.05), ascension of blood glucose induced by adrenalin was inhibited (p < 0.01) and the sugar tolerance of the normal mice was improved. However, the same result did not occur in Ganoderma lucidum and Grifola frondosa group. Compared with Ganoderma rich in vanadium and Grifola frondosa rich in vanadium, the hypoglycemic effects of Coprinus comatus rich in vanadium on hyperglycemic animals are significant; it may be used as a hypoglycemic food or medicine for hyperglycemic people.     

庐山黄山松种群结构及数量动态研究

庐山黄山松(Pinus taiwanensis)广泛分布于海拔800 m以上至山顶地段,在庐山现存植被中占有非常重要的地位。为了更好地了解黄山松在庐山的更新和演替情况,该文通过对庐山黄山松种群的调查,以种群径级结构代替年龄结构,采用"空间代时间"的分析方法,编制庐山黄山松种群的静态生命表,结合种群结构动态指数、时间序列平均推移法模型等方法对黄山松的种群结构和数量动态进行了分析。结果表明:(1)庐山黄山松种群结构呈纺锤形,幼龄和老龄个体数量较少,中龄个体多,目前处于比较稳定的阶段。(2)黄山松种群死亡高峰出现在第8龄级,个体平均期望寿命第2龄级最大,种群存活曲线属于Deevey-Ⅰ型。(3)随着时间的推移,老龄个体逐渐增多,小径级出现缺失,种群表现出衰退趋势。建议在保护区经营和管理的过程中,对黄山松林进行适当的人工抚育,补植一些适宜的落叶阔叶树种,以丰富该地区的树种多样性以及群落结构。     

Heterotrimeric G Proteins Serve as a Converging Point in Plant Defense Signaling Activated by Multiple Receptor-Like Kinases

In fungi and metazoans, extracellular signals are often perceived by G-protein-coupled receptors (GPCRs) and transduced through heterotrimeric G-protein complexes to downstream targets. Plant heterotrimeric G proteins are also involved in diverse biological processes, but little is known about their upstream receptors. Moreover, the presence of bona fide GPCRs in plants is yet to be established. In Arabidopsis (Arabidopsis thaliana), heterotrimeric G protein consists of one Gα subunit (G PROTEIN α-SUBUNIT1), one Gβ subunit (ARABIDOPSIS G PROTEIN β-SUBUNIT1 [AGB1]), and three Gγs subunits (ARABIDOPSIS G PROTEIN γ-SUBUNIT1 [AGG1], AGG2, and AGG3). We identified AGB1 from a suppressor screen of BAK1-interacting receptor-like kinase1-1 (bir1-1), a mutant that activates cell death and defense responses mediated by the receptor-like kinase (RLK) SUPPRESSOR OF BIR1-1. Mutations in AGB1 suppress the cell death and defense responses in bir1-1 and transgenic plants overexpressing SUPPRESSOR OF BIR1-1. In addition, agb1 mutant plants were severely compromised in immunity mediated by three other RLKs, FLAGELLIN-SENSITIVE2 (FLS2), Elongation Factor-TU RECEPTOR (EFR), and CHITIN ELICITOR RECEPTOR KINASE1 (CERK1), respectively. By contrast, G PROTEIN α-SUBUNIT1 is not required for either cell death in bir1-1 or pathogen-associated molecular pattern-triggered immunity mediated by FLS2, EFR, and CERK1. Further analysis of agg1 and agg2 mutant plants indicates that AGG1 and AGG2 are also required for pathogen-associated molecular pattern-triggered immune responses mediated by FLS2, EFR, and CERK1, as well as cell death and defense responses in bir1-1. We hypothesize that the Arabidopsis heterotrimeric G proteins function as a converging point of plant defense signaling by mediating responses initiated by multiple RLKs, which may fulfill equivalent roles to GPCRs in fungi and animals.Receptor-like kinases (RLKs) represent one of the largest protein families in plants and play diverse roles in plant development and stress signaling (Morillo and Tax, 2006). In Arabidopsis (Arabidopsis thaliana), there are over 600 RLKs (Shiu and Bleecker, 2001). Most RLKs contain an extracellular domain, a single transmembrane motif, and a cytoplasmic kinase domain. It is believed that the extracellular domains are involved in ligand recognition that subsequently leads to activation of the cytoplasmic kinase domain. Pathogen-associated molecular pattern (PAMP) receptors FLAGELLIN-SENSITIVE2 (FLS2), Elongation Factor (EF)-TU RECEPTOR (EFR), and CHITIN ELICITOR RECEPTOR KINASE1 (CERK1) all belong to the RLK family. FLS2 and EFR function as receptors for bacterial flagellin and EF-Tu, respectively (Gómez-Gómez and Boller, 2000; Zipfel et al., 2006), while CERK1 is involved in the perception of chitin, a common component of the fungal cell wall (Miya et al., 2007; Wan et al., 2008). CERK1 was also shown to play an important role in defense against bacterial pathogens (Gimenez-Ibanez et al., 2009). Another RLK, Brassinosteroid Insensitive1-associated receptor kinase1 (BAK1), functions as a coreceptor for FLS2 and EFR (Chinchilla et al., 2007; Heese et al., 2007). In addition, a rice (Oryza sativa) RLK, Xa21, functions as the receptor for a peptide derived from AvrXa21 (Song et al., 1995; Lee et al., 2009).Activation of different PAMP receptors often leads to rapid downstream responses, such as oxidative burst, calcium influx, mitogen-activated protein kinase (MAPK) activations, and the up-regulation of defense gene expression (Boller and Felix, 2009). However, our knowledge of how defense responses are regulated downstream of the RLKs remains limited. Genetic analysis of mutants defective in EFR-mediated PAMP responses showed that endoplasmic reticulum (ER) quality control plays an important role in the accumulation of EFR (Li et al., 2009; Lu et al., 2009; Nekrasov et al., 2009; Saijo et al., 2009). ER-resident chaperones are also required for the accumulation of the tobacco (Nicotiana tabacum) INDUCED RECEPTOR-LIKE KINASE (Caplan et al., 2009). BOTRYTIS-INDUCED KINASE1 (BIK1) encodes a cytoplasmic RLK that directly interacts with FLS2 and likely EFR and CERK1 (Lu et al., 2010; Zhang et al., 2010). Knocking out BIK1 leads to modest reductions of PAMP-induced callose deposition, H₂O₂ accumulation, and pathogen resistance. Recently, a group of redundant calcium-dependent protein kinases (CDPKs) were identified as critical regulators of MAPK-independent defense pathways downstream of FLS2 (Boudsocq et al., 2010).In yeast (Saccharomyces cerevisiae) and metazoans, heterotrimeric G proteins, composed of α-, β-, and γ-subunits, serve as essential signaling intermediates between cell surface G-protein-coupled receptors (GPCRs) and their downstream targets (Temple and Jones, 2007). Binding of ligands to GPCRs leads to the exchange of GDP for GTP in the α-subunit, resulting in the activation of the G protein. In Arabidopsis, there is one Gα subunit (G PROTEIN α-SUBUNIT1 [GPA1]), one Gβ subunit (ARABIDOPSIS G PROTEIN β-SUBUNIT1 [AGB1]), and three Gγs subunits (ARABIDOPSIS G PROTEIN γ-SUBUNIT1 [AGG1], AGG2, and AGG3; Temple and Jones, 2007; Chakravorty et al., 2011). Whereas AGG1 and AGG2 are closely related, AGG3 only shares very limited homology to AGG1 and AGG2. GPCR-like proteins have been identified in plants, and their interactions with Gα have been experimentally proven, although their status as bona fide GPCRs remains controversial (Liu et al., 2007; Gookin et al., 2008; Pandey et al., 2009).Heterotrimeric G proteins have been shown to be involved in a wide range of biological processes, including plant immunity (Perfus-Barbeoch et al., 2004). Analysis of rice dwarf1 mutants with defects in the Gα subunit indicates that the rice Gα subunit plays an important role in resistance against rice blast (Suharsono et al., 2002). In Arabidopsis, loss of function of the Gβ or Gγ subunits leads to compromised resistance against the necrotrophic pathogen Plectosphaerella cucumerina (Llorente et al., 2005; Delgado-Cerezo et al., 2012). By contrast, loss of function of the Gα subunit GPA1 results in enhanced resistance against the pathogen (Llorente et al., 2005). Resistance against other necrotrophic pathogens, such as Fusarium oxysporum, Alternaria brassicicola, and Botrytis cinerea, was also found to be compromised in AGB1- and AGG1/AGG2-deficient mutants (Trusov et al., 2006, 2007, 2009). In addition, loss of function of the Gβ subunit leads to reduced elf18-induced resistance against Agrobacterium tumefaciens as well as reduced reactive oxygen species (ROS) production triggered by flagellin22 (flg22) and elf18 (an 18-amino acid peptide that represents the N terminus of bacterial EF-Tu; Ishikawa, 2009). Multiple surface residues of AGB1 were recently shown to play important roles in resistance against necrotrophic pathogens and flg22-induced ROS production (Jiang et al., 2012).Arabidopsis GPA1 was also found to play an important role in stomatal defense. In gpa1 mutants, flg22-induced inhibition of stomatal opening and inward K⁺ channels in guard cells are blocked (Zhang et al., 2008b). Growth of the coronatine-deficient Pseudomonas syringae pv tomato DC3118 is dramatically increased in gpa1 mutant plants (Zeng and He, 2010). In Nicotiana benthamiana, silencing of the Gα and Gβ subunits also leads to reduced elicitor-induced stomatal closure as well as hypersensitive responses induced by harpin (Zhang et al., 2012a).Arabidopsis BAK1-INTERACTING RECEPTOR-LIKE KINASE1 (BIR1) encodes a BAK1-associated RLK (Gao et al., 2009). Knocking out BIR1 results in constitutive activation of cell death and defense responses in a manner that is partially dependent on PHYTOALEXIN DEFICIENT4 (PAD4), a positive regulator of resistance mediated by the Toll-Interleukin-1 Receptor-like-Nucleotide-Binding-Leu-Rich Repeat domain class of resistance proteins. To identify signaling components downstream of BIR1, a suppressor screen was performed in the bir1-1 pad4-1 double-mutant background. A number of suppressor of bir1-1 (sobir) mutants suppressing the seedling lethality phenotype of bir1-1 were identified. SOBIR1 encodes another RLK whose overexpression is sufficient to activate cell death and defense responses (Gao et al., 2009). Combining the sobir1-1 and pad4-1 mutations results in complete suppression of cell death and enhanced pathogen resistance in bir1-1, suggesting that SOBIR1 and PAD4 function in parallel to regulate cell death and defense responses. Here, we report the discovery and characterization of SOBIR2, which encodes the Arabidopsis heterotrimeric G-protein β-subunit AGB1 that functions downstream of SOBIR1 to regulate cell death and defense responses.     

福建闽南地区汉族与畲族的指长比

本文旨在研究福建闽南地区汉族和畲族指长比(R)的特点。随机选择福建闽南地区汉族506例（男性173例,女性333例）,畲族450例（男性231例,女性219例）,采用体质测量法,测量并计算左右侧6项指长比（R_2/3、R_2/4、R_2/5、R_3/4、R_3/5、R_4/5）。福建闽南地区汉族和畲族左、右侧指长比均呈R_2/3<R_2/4<R_3/4<R_2/5<R_4/5<R_3/5的趋势;汉族女性指长比左侧R_2/3、R_2/4、R_2/5、R_3/4、R_3/5和右侧R_2/3、R_2/4、R_2/5高于汉族男性（P<0.05）;畲族女性指长比左侧的R_2/3、R_2/4、R_2/5和右侧R_2/3、R_2/4高于畲族男性（P<0.05）;畲族男性指长比左、右侧R_2/3、R_2/4、R_2/5、R_3/5、R_4/5高于汉族男性（P<0.05）;畲族女性指长比左侧R_2/3、R_2/4和右侧R_2/3、R_2/4、R_2/5、R_4/5高于汉族女性（P<0.05）。同民族不同性别两侧R_2/4百分比分布差异有统计学意义,不同民族同性别右侧R_2/4百分比分布差异有统计学意义。福建闽南地区汉族和畲族指长比存在性别、侧别的不同,与其他地区、族群也存在差异。     

爵床的甲醇提取物对小菜蛾的生物活性作用

为探明爵床(Justicia procumbens)甲醇提取物对小菜蛾的生物活性,采用室内生测法测定了爵床甲醇提取物对小菜蛾的触杀、拒食、胃毒、生长发育抑制和产卵忌避作用。结果表明,爵床甲醇提取物对小菜蛾幼虫具有较强的触杀、拒食、胃毒和生长发育抑制活性,对小菜蛾成虫具有较强的产卵忌避活性。在触杀试验中,药后1、2 d和3 d爵床甲醇提取物对小菜蛾3龄幼虫的致死中浓度(LC50)分别为5.17、4.05和3.06 mg/m L;在拒食试验中,药后1 d和2 d提取物对3龄幼虫的选择性拒食中浓度(AFC50)分别为2.64和3.13 mg/m L,药后1 d和2 d提取物对3龄幼虫的非选择性拒食中浓度(AFC50)分别为3.70、4.54 mg/m L;在胃毒试验中,药后4、5、6 d和7 d提取物对3龄幼虫的致死中浓度(LC50)分别为8.13、3.65、2.88、2.23 mg/m L;在生长发育抑制试验中,药后1 d和2 d提取物对3龄幼虫的抑制中浓度(IC50)分别为2.02、1.40 mg/m L;在产卵忌避试验中,药后1、2 d和3 d提取物对小菜蛾成虫的选择性产卵忌避中浓度(AOC50)分别为2.61、3.66、4.58 mg/m L,药后1、2和3 d提取物对小菜蛾成虫的非选择性产卵忌避中浓度(AOC50)分别为3.19、4.52、5.65 mg/m L。由此证实,爵床提取物对小菜蛾具有显著的毒杀活性,具有开发为新型高效、低毒植物源农药的潜在价值。     

Combination of mTOR and EGFR Kinase Inhibitors Blocks mTORC1 and mTORC2 Kinase Activity and Suppresses the Progression of Colorectal Carcinoma

Mammalian target of rapamycin complex 1 and 2 (mTORC1/2) are overactive in colorectal carcinomas; however, the first generation of mTOR inhibitors such as rapamycin have failed to show clinical benefits in treating colorectal carcinoma in part due to their effects only on mTORC1. The second generation of mTOR inhibitors such as PP242 targets mTOR kinase; thus, they are capable of inhibiting both mTORC1 and mTORC2. To examine the therapeutic potential of the mTOR kinase inhibitors, we treated a panel of colorectal carcinoma cell lines with PP242. Western blotting showed that the PP242 inhibition of mTORC2-mediated AKT phosphorylation at Ser 473 (AKT^S473) was transient only in the first few hours of the PP242 treatment. Receptor tyrosine kinase arrays further revealed that PP242 treatment increased the phosphorylated epidermal growth factor receptor (EGFR) at Tyr 1068 (EGFR^T1068). The parallel increase of AKT^S473 and EGFR^T1068 in the cells following PP242 treatment raised the possibility that EGFR phosphorylation might contribute to the PP242 incomplete inhibition of mTORC2. To test this notion, we showed that the combination of PP242 with erlotinib, an EGFR small molecule inhibitor, blocked both mTORC1 and mTORC2 kinase activity. In addition, we showed that the combination treatment inhibited colony formation, blocked cell growth and induced apoptotic cell death. A systemic administration of PP242 and erlotinib resulted in the progression suppression of colorectal carcinoma xenografts in mice. This study suggests that the combination of mTOR kinase and EGFR inhibitors may provide an effective treatment of colorectal carcinoma.