天然橡胶（Natural rubber）是一种生物高分子聚合物，由于具有独特的理化性质而成为重要的工业原料及不可替代的战略物资。巴西橡胶树（Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg.）是目前商业化天然橡胶的唯一来源，主要生长在东南亚热带及亚热带地区的种植园中。然而，目前巴西橡胶树的产量难以满足急剧增长的全球工业对天然橡胶的迫切需求。以石油为加工原料的合成橡胶（Synthetic rubber）部分补充天然橡胶产量的不足，但其工业性能无法比拟天然橡胶。因此，亟需开发具有更广泛环境适应性的天然橡胶新作物。本文综述了园艺植物-橡胶草（Taraxacum kok-saghyz Rodin）和莴苣（Lactuca L. species），木本植物-银胶菊（Parthenium argentatum A. Gray）和杜仲（Eucommia ulmoides Oliv.）以及其它有生产天然橡胶潜力的植物的研究进展。本综述以基因组学、转录组学、蛋白质组学和代谢组学等多维组学研究，以及天然橡胶生物合成分子机制为重点，讨论了基于现代生物技术的多维整合策略在解析天然橡胶生物合成机制方面的广阔前景，为加速天然橡胶新作物的培育提供借鉴。

    The structural characteristics of protein body accumulation in different endosperm regions of hard wheat cultivar (XM33) and soft wheat cultivar (NM13) under drought stress were investigated. Drought stress treatment was implemented from plant regreening to the caryopsis mature stage. Microscope images of endosperm cells were obtained using resin semi-thin slice technology to observe the distribution and relative area of protein body (PB). Compared with NM13, relative PB area of XM33 was significantly higher in sub-aleurone endosperm region. The amount of accumulation, including the size and relative area of PB, in two wheat cultivars was higher in sub-aleurone region than that in central region at 18 days post anthesis (DPA). Drought stress significantly enhanced the sizes and relative areas of PBs in the dorsal and abdominal endosperms in two wheat cultivars. Particularly for dorsal endosperm, drought stress enhanced the relative PB area at 18 DPA and NM13 (5.0% vs. 6.73%) showed less enhancement than XM33 (5.49% vs. 8.96%). However, NM13 (9.58% vs. 12.02%) showed greater enhancement than XM33 (10.25% vs. 11.7%) at 28 DPA. The protein content in the dorsal and abdominal endosperms of the two wheat cultivars decreased at 12 DPA and then increased until 38 DPA. Drought stress significantly increased the protein contents in the two main regions. From 12 to 38 DPA, the amount of PB accumulation and the protein content were higher in XM33 than those in NM13. The results revealed that PB distribution varied in different endosperm tissues and that the amount of PB accumulation was remarkably augmented by drought stress.

The aldehyde dehydrogenase (ALDH) superfamily of NAD(P)+-dependent enzymes, in general, oxidize a wide range of endogenous and exogenous aliphatic and aromatic aldehydes to their corresponding carboxylic acids and play an essential role in detoxification of reactive oxygen species (ROS) accumulated under the stressed conditions. In order to identify genes required for the stresses responses in the grass crop Oryza sativa, a homologue of ALDH gene (OsALDH22) was isolated and characterized. OsALDH22 is conserved in eukaryotes, shares high homology with the orthologs from aldehyde dehydrogenase subfamily ALDH22. The OsALDH22 encodes a protein of 597 amino acids that in plants exhibit high identity with the orthologs from Zea mays, Sorghum bicolor, Hordeum vulgare and Arabidopsis thaliana, respectively, and the conserved amino acid characteristics for ALDHs are present, including the possible NAD+ binding site (F-V-G-SP- G-V-G), the catalytic site (V-T-L-E-L-G-G-K) and the Cys active site. Semi-quantitative PCR and real-time PCR analysis indicates that OsALDH22 is expressed differentially in different tissues. Various elevated levels of OsALDH22 expression have been detected when the seedlings exposed to abiotic stresses including dehydration, high salinity and abscisic acid (ABA). Transgenic rice plants overexpressing OsALDH22 show elevated stresses tolerance. On the contrary, downregulation of OsALDH22 in the RNA interference (RNAi) repression transgenic lines manifests declined stresses tolerance.