Physiological, anatomical and biochemical characterisation of photosynthetic types in genus Cleome (Cleomaceae).
Physiological, anatomical and biochemical characterisation of photosynthetic types in genus Cleome (Cleomaceae).
复制标题
Cleome 属（Cleomacaceae）光合类型的生理、解剖和生化特征。
作者：
E. Voznesenskaya;N. Koteyeva;S. Chuong;A. Ivanova;J. Barroca;L. Craven;G. Edwards
C4光合作用在陆地植物的18个不同的科中已经进化了许多次，在叶片解剖学上有很大的变化，从各种形式的Kranz解剖学到在单一类型的光合细胞内发生的C4光合作用。目前对醉蝶花科植物的光合分型研究较少，仅发现一种C4植物，即白醉蝶花。最近人们对选择和开发来自Cleomaceae科的C4物种作为C4模型系统感兴趣，因为它与拟南芥（Arabidopsis）（C3模型系统）最密切相关（Brown等人，2005）。通过对230多个Cleomaceae植物样品的碳同位素组成（δ 13 C）的测定，我们又鉴定出两个C4植物，C.沙枣（Africa）和C.作者声明：（澳大利亚）。其他几个物种的δ 13 C值在-17‰ ~-19‰之间，表明它们是类C4或中间物种。对8种醉蝶花属植物进行了生理、解剖和生化分析。其中包括C。gynandra，一种NAD-苹果酸酶（NAD-ME）类型C4种; paradoxa R.Br.，一个C3-C4中间物种，和6个被表征为C3物种的其他物种。醉蝶花具有C4特征，其基于低CO2补偿点（Γ）、C4型δ 13 C值、Kranz型叶解剖和维管束鞘（BS）超微结构、C4途径酶的存在以及Rubisco和磷酸烯醇丙酮酸羧化酶的选择性免疫定位。根据中间体Γ（27.5 μmol mol-1）、超微结构特征和光呼吸途径中甘氨酸脱羧酶在BS细胞线粒体中的选择性定位，将白花菜鉴定为C3-C4中间体。其他六个物种是C3植物的基础上的Γ，δ 13 C值，非克兰兹叶解剖，和C4途径酶的水平（非常低或不存在）典型的C3植物。结果表明，这是一个有趣的家庭，研究C4光合作用的遗传基础和C3物种的进化。
C4 photosynthesis has evolved many times in 18 different families of land plants with great variation in leaf anatomy, ranging from various forms of Kranz anatomy to C4 photosynthesis occurring within a single type of photosynthetic cell. There has been little research on photosynthetic typing in the family Cleomaceae, in which only one C4 species has been identified, Cleome gynandra L. There is recent interest in selecting and developing a C4 species from the family Cleomaceae as a model C4 system, since it is the most closely related to Arabidopsis, a C3 model system (Brown et al. 2005). From screening more than 230 samples of Cleomaceae species, based on a measure of the carbon isotope composition (δ13C) in leaves, we have identified two additional C4 species, C. angustifolia Forssk. (Africa) and C. oxalidea F.Muell. (Australia). Several other species have δ13C values around -17‰ to -19‰, suggesting they are C4-like or intermediate species. Eight species of Cleome were selected for physiological, anatomical and biochemical analyses. These included C. gynandra, a NAD-malic enzyme (NAD-ME) type C4 species, C. paradoxa R.Br., a C3-C4 intermediate species, and 6 others which were characterised as C3 species. Cleome gynandra has C4 features based on low CO2 compensation point (Γ), C4 type δ13C values, Kranz-type leaf anatomy and bundle sheath (BS) ultrastructure, presence of C4 pathway enzymes, and selective immunolocalisation of Rubisco and phosphoenolpyruvate carboxylase. Cleome paradoxa was identified as a C3-C4 intermediate based on its intermediate Γ (27.5 μmol mol-1), ultrastructural features and selective localisation of glycine decarboxylase of the photorespiratory pathway in mitochondria of BS cells. The other six species are C3 plants based on Γ, δ13C values, non-Kranz leaf anatomy, and levels of C4 pathway enzymes (very low or absent) typical of C3 plants. The results indicate that this is an interesting family for studying the genetic basis for C4 photosynthesis and its evolution from C3 species.