Brand Arnon, Shirding Neti, Shleizer Sharona, Ori Naomi
The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Otto Warburg Minerva Center for Agricultural Biotechnology, The Hebrew University of Jerusalem, Rehovot, Israel.
Planta. 2007 Sep;226(4):941-51. doi: 10.1007/s00425-007-0540-0. Epub 2007 May 23.
Balancing shoot apical meristem (SAM) maintenance and organ formation from its flanks is essential for proper plant growth and development and for the flexibility of organ production in response to internal and external cues. Leaves are formed at the SAM flanks and display a wide variability in size and form. Tomato (Solanum lycopersicum) leaves are compound with lobed margins. We exploited 18 recessive tomato mutants, representing four distinct phenotypic classes and six complementation groups, to track the genetic mechanisms involved in meristem function and compound-leaf patterning in tomato. In goblet (gob) mutants, the SAM terminates following cotyledon production, but occasionally partially recovers and produces simple leaves. expelled shoot (exp) meristems terminate after the production of several leaves, and these leaves show a reduced level of compoundness. short pedicel (spd) mutants are bushy, with impaired meristem structure, compact inflorescences, short pedicels and less compound leaves. In multi drop (mud) mutants, the leaves are more compound and the SAM tends to divide into two active meristems after the production of a few leaves. The range of leaf-compoundness phenotypes observed in these mutants suggests that compound-leaf patterning involves an array of genetic factors, which act successively to elaborate leaf shape. Furthermore, the results indicate that similar mechanisms underlie SAM activity and compound-leaf patterning in tomato.
平衡茎尖分生组织（SAM）的维持及其侧面的器官形成，对于植物的正常生长发育以及响应内部和外部信号时器官产生的灵活性至关重要。叶片在SAM侧面形成，并且在大小和形态上表现出很大的变异性。番茄（Solanum lycopersicum）叶片为复叶，边缘有裂片。我们利用了18个隐性番茄突变体，它们代表四个不同的表型类别和六个互补组，来追踪番茄中参与分生组织功能和复叶模式形成的遗传机制。在杯状（gob）突变体中，SAM在子叶产生后终止，但偶尔会部分恢复并产生单叶。逐出茎（exp）分生组织在几片叶子产生后终止，并且这些叶子的复叶程度降低。短花梗（spd）突变体呈丛生状，分生组织结构受损，花序紧凑，花梗短，复叶较少。在多叶（mud）突变体中，叶子的复叶程度更高，并且SAM在几片叶子产生后倾向于分裂为两个活跃的分生组织。在这些突变体中观察到的叶复叶程度表型范围表明，复叶模式形成涉及一系列遗传因素，这些因素依次作用以细化叶片形状。此外，结果表明类似的机制是番茄中SAM活性和复叶模式形成的基础。
