Activity and distribution of carbonic anhydrase in leaf and ear parts of wheat ( Triticum aestivumL.)

• Published in: Plant science (Limerick) 2004, Vol.166 (3), p.627-632
• Main Authors: Li, Xingjun, Hou, Jihua, Bai, Kezhi, Yang, Xinghong, Lin, Jinxing, Li, Zhensheng, Kuang, Tingyun
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Bundle sheath cells; C 4 photosynthesis; carbonate dehydratase; Carbonic anhydrase; developmental stages; Economic plant physiology; enzyme activity; Fundamental and applied biological sciences. Psychology; grain crops; Histochemical staining; leaves; Metabolism; Net assimilation, photosynthesis, carbon metabolism. Photorespiration, respiration, fermentation (anoxia, hypoxia); Non-leaf tissue; Nutrition. Photosynthesis. Respiration. Metabolism; Photosynthesis, respiration. Anabolism, catabolism; plant development; Plant physiology and development; plant proteins; tissue distribution; Triticum aestivum; wheat; Winter wheat ( Triticum aestivum L.)
• ISSN: 0168-9452; 1873-2259
• DOI: 10.1016/j.plantsci.2003.10.031

The activity of carbonic anhydrase (CA; EC 4.2.1.1.) was examined in leaf and ear parts of wheat plants ( Triticum aestivum L.) using physiological measurement and histochemical staining. CA activity in leaves increased to the maximum at flag-leaf visible stage, and then decreased to a minimum before increasing at dough stage. From milk to dough stage, CA activities tended to decrease in both glumes and paleas, but increased in the lemmas and pericarps. CA activities in the tissues of ear parts at milk stage were higher than that in leaf tissue, and cv. Xiaoyan54 possessed higher activity of CA in flag-leaves, glumes, lemmas and pericarps than cv. Jing411 at dough stage. Histochemical staining indicates that CA was localized mainly in the chloroplasts of mesophyll cells in flag-leaves and glumes, and also in the xylem vessels of vascular bundles and cytosol of mesophyll cells in lemmas and paleas, but little CA activity was found in the bundle sheath cells (BSC) of both flag-leaf and ear parts. The results suggest that the presence of CA in the mesopyll chloroplasts of glumes, as well as in the xylem vessels of vascular bundles and cytosol of mesophyll cells in lemmas and paleas, might play a functional role for C 4 photosynthesis at dough stage of wheat plants, and cv. Xiaoyan54 had a higher rate of CO 2 delivery than cv. Jing411.