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Summary The plant hormone auxin and its directional intercellular transport play a major role in diverse aspects of plant growth and development. The establishment of auxin gradients requires the asymmetric distribution of members of the auxin efflux carrier PIN‐FORMED (PIN) protein family to the plasma membrane. An endocytic pathway regulates the recycling of PIN proteins between the plasma membrane and endosomes, providing a mechanism for dynamic localisation. N‐Ethylmaleimide‐sensitive factor adaptor protein receptors (SNAP receptors, SNAREs) mediate fusion between vesicles and target membranes and are classed as Q‐ or R‐SNAREs based on their sequence. We analysed gain‐ and loss‐of‐function mutants, dominant‐negative transgenics and localisation of the Arabidopsis R‐SNARE VAMP714 protein to understand its function.We demonstrate that VAMP714 is essential for the insertion of PINs into the plasma membrane, for polar auxin transport, root gravitropism and morphogenesis. VAMP714 gene expression is upregulated by auxin, and the VAMP714 protein co‐localises with endoplasmic reticulum and Golgi vesicles and with PIN proteins at the plasma membrane.It is proposed that VAMP714 mediates the delivery of PIN‐carrying vesicles to the plasma membrane, and that this forms part of a positive regulatory loop in which auxin activates a VAMP714‐dependent PIN/auxin transport system to control development.

Background Communication systems within and between plant cells involve the transfer of ions and molecules between compartments, and are essential for development and responses to biotic and abiotic stresses. This is turn requires the regulated movement and fusion of membrane systems with their associated cargo. Recent advances in genomics has provided new resources with which to investigate the evolutionary relationships between membrane proteins across plant species. Results Members of the soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) are known to play important roles in vesicle trafficking across plant, animal and microbial species. Using recent public expression and transcriptomic data from nine representative green plants, we investigated the evolution of the SNARE classes and linked protein changes to functional specialization (expression patterns). We identified an additional three putative SNARE genes in the model plant Arabidopsis. We found that all SNARE classes have expanded in number to a greater or lesser degree alongside the evolution of multicellularity. Sub-functionalization of SNARE family members to different tissues, associated with an accumulation of protein changes is typical, although at least one example of neo-functionalization between the R-SNAREs VAMP722 and VAMP723 was also observed. Conclusion These results provide an insight into SNARE protein evolution and functional specialization. The work provides a platform for hypothesis-building and future research into the precise functions of these proteins in plant development and responses to the environment.

Supplemental material, 2873cc8b46636_EvoBioRevSupplTable4_xyz466366e8025bf for Vesicle Transport in Plants: A Revised Phylogeny of SNARE Proteins by Xiaoyan Gu, Adrian Brennan, Wenbin Wei, Guangqin Guo and Keith Lindsey in Evolutionary Bioinformatics

Supplemental material, 529d24f646636_EvoBioRevSupplTable6_xyz466362abe5173 for Vesicle Transport in Plants: A Revised Phylogeny of SNARE Proteins by Xiaoyan Gu, Adrian Brennan, Wenbin Wei, Guangqin Guo and Keith Lindsey in Evolutionary Bioinformatics

Supplemental material, ef0a8cf646636_EvoBioRevSupplTable3y_xyz466366d196b73 for Vesicle Transport in Plants: A Revised Phylogeny of SNARE Proteins by Xiaoyan Gu, Adrian Brennan, Wenbin Wei, Guangqin Guo and Keith Lindsey in Evolutionary Bioinformatics

Supplemental material, 3185449246636_EvoBioRevSupplTable1_xyz466364bc83175 for Vesicle Transport in Plants: A Revised Phylogeny of SNARE Proteins by Xiaoyan Gu, Adrian Brennan, Wenbin Wei, Guangqin Guo and Keith Lindsey in Evolutionary Bioinformatics

Supplemental material, f763b0b446636_EvoBioRevSupplTable2_xyz46636386aed71 for Vesicle Transport in Plants: A Revised Phylogeny of SNARE Proteins by Xiaoyan Gu, Adrian Brennan, Wenbin Wei, Guangqin Guo and Keith Lindsey in Evolutionary Bioinformatics

Supplemental material, 00f8b8c046636_EvoBioRevSupplTable5y_xyz466362fa485fb for Vesicle Transport in Plants: A Revised Phylogeny of SNARE Proteins by Xiaoyan Gu, Adrian Brennan, Wenbin Wei, Guangqin Guo and Keith Lindsey in Evolutionary Bioinformatics

SummaryThe plant hormone auxin and its directional intercellular transport plays a major role in diverse aspects of plant growth and development. The establishment of auxin gradients in plants requires asymmetric distribution of members of the auxin efflux carrier PIN-FORMED (PIN) protein family to the plasma membrane. An endocytic pathway regulates the recycling of PIN proteins between the plasma membrane and endosomes, providing a mechanism for dynamic localization.N-ethylmaleimide-sensitive factor adaptor protein receptors (SNAP receptors, SNAREs) mediate fusion between vesicles and target membranes and are classed as Q- or R-SNAREs based on their sequence. We analysed gain- and loss-of-function mutants, dominant negative transgenics and protein localization of the Arabidopsis R-SNARE VAMP714 to understand its function.We demonstrate that VAMP714 is essential for the insertion of PINs into the plasmamembrane, for polar auxin transport, and for root gravitropism and morphogenesis.VAMP714gene expression is upregulated by auxin, and the VAMP714 protein co-localizes with ER and Golgi vesicles and with PIN proteins at the plasma membrane.It is proposed that VAMP714 mediates the delivery of PIN-carrying vesicles to the plasma membrane, and that this forms part of a positive regulatory loop in which auxin activates a VAMP714-dependent PIN/auxin transport system to control development.

The combined effect of gallic acid (3,4,5-trihydroxy benzoic acid; GA; 50 mg kg(-1) i.p.) and propolis (200 mg kg(-1) p.o.) was evaluated against beryllium-induced biochemical and morphological alterations in the liver and kidney. Female albino rats were exposed to beryllium nitrate (1 mg kg(-1) i.p.) daily for 28 days followed by treatment with the above mentioned therapeutic agents either individually or in combination for five consecutive days. Exposure to beryllium increased its concentration in the serum, liver and kidney and caused significant alterations in cytochrome P450 enzymes, microsomal lipid peroxidation and protein contents. Beryllium administration significantly altered the aspartate aminotransaminase, alanine aminotransaminase, lactate dehydrogenase, γ-grutamy1 transpeptidase, bilirubin, creatinine and urea in serum, and the activity of acid phosphatase, alkaline phosphatase, adenosine triphosphatase, glucose-6-phophatase and succinic dehydrogenase, triglycerides, cholesterol, protein contents, glycogen contents, lipid peroxidation and glutathione level in the liver and kidney. Beryllium exposure induced severe alterations in hepatorenal morphology, revealing its toxic consequences at a cellular level. Individual administration of GA and propolis reduced the effects on the studied parameters to a degree. Interestingly, GA in conjunction with propolis reversed the alterations in all of the variables examined, highlighting the beneficial effects of combined therapy over monotherapy in the alleviation of beryllium-induced systemic toxicity.

Nuclear migration is a non-random movement of nucleus toward specific site in the cell in many eukaryotes and essential to normal cellular activities of growth, division and development. It is shown that cytoskeleton and its associated proteins are involved in this process, which have been best analyzed in yeast and filamentous fungi but just started in higher plants. The purpose of this review is to comment the advances in this field.

Cytology at meiotic prophase I in pollen mother cells (PMCs) of the euploid wheat and its 21 nullisomic lines were investigated. The results revealed that all of the investigated materials had cytomixis between their PMCs, and in most lines the PMCs within a loculus of an anther developed synchronously, but asynchrony was observed in five nullisomic lines of 5A, 5B, 2D, 4D and 5D, suggesting that genes controlling meiotic synchrony among PMCs were localized on these chromosomes. Meiotic asynchrony could occur even between two neighboring pollen mother cells (PMCs) undergoing cytomixis, suggesting that cytomictic channels (CCs) alone could not sufficiently render the occurrence of this prominent phenomenon, and that some other factors must be involved in this process.

Great progress has been made in recent years in studies on the mechanism ofAgrobacterium-medicated transformation and its application. Many details of the key molecular events within the bacterial cells involved in T-DNA transfer have been elucidated, and it is notable that some plant factors which were elusive before are purified and characterized. Vast kinds of species, which were either recalcitrant to or not included in the host range ofAgrobacterium, can now be transformed by this bacterium, and they include the very important cereal species, gymnosperms, yeast and many filamentous fungi. The simplein vivo transformation of tissue in intact plants and the “agrolistic” methods to transform recalcitrant plants are the two novel technical achievements. Combined with other powerful techniques such as bacterial artificial chromosome, very large DNA fragment can be transformed into the plant genome byAgrobacterium. Further studies will elucidate more plant-encoded factors involved in T-DNA transformation and there is a need to develop more powerfulAgrobacterium-based transformation systems to meet different needs in basic research and crop improvement practice.

Epigenetic marks in the form of DNA methylation are involved in the development of germ cells and are important in the maintenance of fertility. However, the controlling system of the on-off switch for DNA methylation largely remains unclear. In this study, the extent of cytosine methylation during the meiotic prophase I in David lily is assessed using high pressure liquid chromatography to evaluate the DNA methylation rates. Comparing the degree of DNA methylation before, during, and after synizesis, both de novo methylation and demethylation occurred. Mainly the methylation level decreased by 21.3% (from 54.8 to 33.5%) during synizesis in the pollen mother cells. The developmental timing of genome-wide DNA methylation acquisition during pollen mother cell development is clarified in this paper. The relative amounts of 5-methyl-deoxycytidine of global methylation in leaf DNA in David lily were also higher than in other species reported.