采用光学和电子显微镜技术、十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)技术分离鉴定热带落叶树木印度紫檀营养贮藏蛋白质(VSPs)，并采用免疫印迹技术分析包括印度紫檀在内的5种热带树木VSPs之间的免疫相关性。结果表明：印度紫檀VSPs包括4种蛋白质，分子质量分别为33.5、28、21和19.5 ku；它们主要分布在枝条木薄壁细胞、木射线薄壁细胞、韧皮薄壁细胞和韧皮射线薄壁细胞、皮层薄壁细胞以及树干、大根的韧皮薄壁细胞和韧皮射线薄壁细胞中；它们的超微结构存在明显差异，大致可以分为电子致密的团块状、絮状和均一状3种形态，不同形态的VSPs存在于不同的贮藏蛋白质细胞中，具有细胞特异性；在新梢发育时期，积累在枝条中的VSPs明显消失，但积累在树干和大根中的VSPs和落叶期相比没有明显变化，积累在枝条中的营养贮藏蛋白质是新梢生长发育所需氮素的主要来源；同一科树木的营养贮藏蛋白质之间存在较强的免疫相关性，但不同科树木的营养贮藏蛋白质之间缺乏免疫相关性。树木营养贮藏蛋白质生化性质的多样性可能反映了生物学功能的多样性。
Vegetative storage proteins (VSPs)in Pterocarpus indicus，a tropical leguminosae tree，were identified by using optical and electronic microscopy and SDS-PAGE．The immuno-relatedness of VSPs in five tropical trees was also examined by Western-blotting．Under optical microscope，abundant vacuolar inclusions in fresh blue appearance were found in the xylem parenehyma cells，xylem ray parenchyma ceils，phloem parenchyma cells，phloem ray parenchyma cells and cortical parenchyma cells in terminal branches and also observed in the phloem parenchyma cells and phloem ray parenchyma cells in trunk and large roots stained with mercury-bromphenol blue specific for general proteins during leafless stage．So，the vacuolar inclusions were obviously proteinaceous and the cells containing vacuolar protein inclusions were referred as protein-storing cells(PSCs)．Under an electron microscope，nubbly，floccular and homogenous forms of VSPs could be distinguished in the phloem parenchyma cells of terminal branches during leafless stage and their distribution was cell-specific．The protein inclusions in PSCs of the bark of branches almost disappeared during new shoot development while those in the trunk and large roots had no detectable changes in abundance．There were four prominent protein bands with molecular masses of about 33.5，28，21 and 19.5 ku respectively in the SDS-PAGE profiles of soluble protein from the bark tissues of branches．Trunk and large roots during leafless period．The four proteins in the bark tissues of branches decreased obviously during new shoot development whereas were present in abundance in the bark tissues of trunk and large roots．Based on the data above，the four proteins were the VSPs in P．Ind／cus．With the polyclonal antibodies raised against the 21 ku VSP in Swietenia macrophylla (Meliaceae)，the 22 ku VSP in Litchi chinensis (Sapindaceae)and the 67 ku VSP in Hevea brasiliensis (Euphorbiaceae)，immuno-relatedness were revealed by Western-blotting between the VSPs in Pterocarpus indicus，Swietenia macrophyUa，Litchi chinensis，Sapindus mukorossi，and Hevea brasiliensis． There was strong immuno-relatedness of the VSPs in different tree species of the same family and no immuno-relatedness between the VSPs in the hardwoods of different families．The diversity of VSPs in biochemical character suggested that VSPs in trees have some special roles in addition to nitrogen storage．
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