Laurenzi M, Tipping A J, Marcus S E, Knox J P, Federico R, Angelini R, McPherson M J
Dipartimento di Biologia, Università degli Studi Roma Tre, Viale Guglielmo Marconi 446, 00146 Rome, Italy.
Planta. 2001 Nov;214(1):37-45. doi: 10.1007/s004250100600.
Copper-containing amine oxidase (CuAO) has been proposed to play a role in H2O2 production in plant cell walls during cell development and in response to pathogen attack. We have compared the localisation of CuAO in pea (Pisum sativum L.), lentil (Lens culinaris M.) and chick pea (Cicer arietinum L.) grown under different light conditions, using both immuno- and histochemical techniques. The enzyme was detected by indirect immunofluorescence in the cell walls of parenchyma tissues of etiolated pea and lentil plants and was particularly abundant at intercellular spaces. Upon de-etiolation, CuAO largely disappeared from cortical cell walls except in the region of intercellular spaces. In the apical internode of light-grown seedlings, CuAO occurred mainly in cortical cell walls and, to some extent, in cell walls of xylem vessels. In both the elongation zone and mature regions of roots, CuAO was restricted to cortical cell walls and some cell junctions close to the meristem. Extensin epitopes co-localised to intercellular spaces of the cortex in de-etiolated pea, indicating that CuAO may have a role in cell wall strengthening at intercellular spaces. In chick pea, the localisation of the enzyme varied between different cultivars that have differing susceptibility to the fungus Ascochyta rabiei. In a susceptible cultivar Calia, immunogold labelling localised CuAO to cell walls of the cortex, as in lentil and pea, while in a resistant cultivar Sultano, it was most abundant in xylem vessels and, in light-grown plants, in the epidermis. These expression patterns are discussed with regard to the possible functions of amine oxidase in cell growth, cell differentiation and pathogen resistance.
含铜胺氧化酶（CuAO）被认为在植物细胞壁细胞发育过程中以及应对病原体攻击时产生过氧化氢的过程中发挥作用。我们使用免疫和组织化学技术，比较了在不同光照条件下生长的豌豆（Pisum sativum L.）、扁豆（Lens culinaris M.）和鹰嘴豆（Cicer arietinum L.）中CuAO的定位。通过间接免疫荧光在黄化豌豆和扁豆植物薄壁组织的细胞壁中检测到该酶，并且在细胞间隙中特别丰富。去黄化后，除了细胞间隙区域外，CuAO在皮层细胞壁中基本消失。在光照生长的幼苗的顶端节间，CuAO主要出现在皮层细胞壁中，并且在一定程度上出现在木质部导管的细胞壁中。在根的伸长区和成熟区，CuAO都局限于皮层细胞壁和靠近分生组织的一些细胞连接处。伸展蛋白表位与去黄化豌豆皮层的细胞间隙共定位，表明CuAO可能在细胞间隙的细胞壁强化中起作用。在鹰嘴豆中，该酶的定位在对真菌Ascochyta rabiei敏感性不同的不同品种之间有所不同。在易感品种Calia中，免疫金标记将CuAO定位到皮层细胞壁，如在扁豆和豌豆中一样，而在抗性品种Sultano中，它在木质部导管中最丰富，并且在光照生长的植物中，在表皮中最丰富。本文讨论了这些表达模式与胺氧化酶在细胞生长、细胞分化和病原体抗性中的可能功能的关系。
