Substantial role for carbonic anhydrase in latitudinal variation in mesophyll conductance of Populus trichocarpa Torr. & Gray.
Substantial role for carbonic anhydrase in latitudinal variation in mesophyll conductance of Populus trichocarpa Torr. & Gray.
复制标题
碳酸酐酶在毛果杨叶肉电导纬度变化中的重要作用。
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
R. Guy
中科院分区：
文献类型：
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作者：
M. Momayyezi;R. Guy
在黑棉白杨中，净光合作用（An）随纬度而变化，在北方基因型中，支持较高的气孔导度（gs）。我们在这里报告一个平行的渐变叶肉电导率（gm）和碳酸酐酶（CA）活性的变化。同时使用碳同位素歧视和叶绿素荧光方法，我们研究了乙酰唑胺，CA的抑制剂，对通用汽车在六个代表性的基因型（三个从南北渐变的两端）的影响。乙酰唑胺降低CA活性，gm，gs，叶绿体CO2浓度（Cc）和在正常CO2（400 μmol mol-1），后者是可逆的饱和CO2。北方基因型的An、gm和CA活性的绝对下降幅度大于南方基因型（P < 0.025），但下降百分比相似。相反，与南方基因型相比，北方基因型表现出较低的Cc降低百分比（P < 0.025）。北方基因型的CA活性相对于叶面积（2倍）和叶质量（1.8倍）均显著高于其它基因型（P < 0.016）。CA活性与gm之间的关系是相似的，无论是固有的或抑制剂诱导的变化。我们认为，更大的CA活性有助于更高的gm在北方P.大果海棠基因型，但其他扩散途径的组件也可能参与。
In Populus trichocarpa (black cottonwood), net photosynthesis (An ) varies with latitude and, in northern genotypes, is supported by higher stomatal conductance (gs ). We report here a parallel cline in mesophyll conductance (gm ) and link this variation to carbonic anhydrase (CA) activity. Using concurrent carbon isotope discrimination and chlorophyll fluorescence methods, we examined the effects of acetazolamide, an inhibitor of CA, on gm in six representative genotypes (three from either end of the north-south cline). Acetazolamide reduced CA activity, gm , gs , chloroplast CO2 concentration (Cc ) and An at normal CO2 (400 μmol mol-1 ), the latter being reversible at saturating CO2 . Absolute reductions in An , gm and CA activity were greater in northern genotypes than in southern genotypes (P < 0.025) but percent reductions were similar. In contrast, northern genotypes showed lower percent reduction in Cc compared to southern genotypes (P < 0.025). The northern genotypes had greater CA activity relative to both leaf area (two-fold) and mass (1.8-fold) (P < 0.016). The relationship between CA activity and gm was similar whether the variation was inherent or inhibitor induced. We suggest that greater CA activity contributes to higher gm in northern P. trichocarpa genotypes, but other diffusion pathway components may also be involved.
影响因子：
4.1
作者：
HewettEmmett, D;Tashian, RE
通讯作者：
Tashian, RE