Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València - Consejo Superior de Investigaciones Científicas, Ingeniero Fausto Elio s/n, 46022, Valencia, Spain.
Facultad Ciencias de la Salud, Universidad Cooperativa de Colombia, Carrera 35#36-99, Barrio Barzal, Villavicencio, Colombia.
BMC Plant Biol. 2019 Apr 15;19(1):141. doi: 10.1186/s12870-019-1735-9.
Tomato mutants altered in leaf morphology are usually identified in the greenhouse, which demands considerable time and space and can only be performed in adequate periods. For a faster but equally reliable scrutiny method we addressed the screening in vitro of 971 T-DNA lines. Leaf development was evaluated in vitro in seedlings and shoot-derived axenic plants. New mutants were characterized in the greenhouse to establish the relationship between in vitro and in vivo leaf morphology, and to shed light on possible links between leaf development and agronomic traits, a promising field in which much remains to be discovered.
Following the screening in vitro of tomato T-DNA lines, putative mutants altered in leaf morphology were evaluated in the greenhouse. The comparison of results in both conditions indicated a general phenotypic correspondence, showing that in vitro culture is a reliable system for finding mutants altered in leaf development. Apart from providing homogeneous conditions, the main advantage of screening in vitro lies in the enormous time and space saving. Studies on the association between phenotype and nptII gene expression showed co-segregation in two lines (P > 99%). The use of an enhancer trap also allowed identifying gain-of-function mutants through reporter expression analysis. These studies suggested that genes altered in three other mutants were T-DNA tagged. New mutants putatively altered in brassinosteroid synthesis or perception, mutations determining multiple pleiotropic effects, lines affected in organ curvature, and the first tomato mutant with helical growth were discovered. Results also revealed new possible links between leaf development and agronomic traits, such as axillary branching, flower abscission, fruit development and fruit cracking. Furthermore, we found that the gene tagged in mutant 2635-MM encodes a Sterol 3-beta-glucosyltransferase. Expression analysis suggested that abnormal leaf development might be due to the lack-off-function of this gene.
In vitro culture is a quick, efficient and reliable tool for identifying tomato mutants altered in leaf morphology. The characterization of new mutants in vivo revealed new links between leaf development and some agronomic traits. Moreover, the possible implication of a gene encoding a Sterol 3-beta-glucosyltransferase in tomato leaf development is reported.
番茄叶片形态发生改变的突变体通常是在温室中鉴定的，这需要大量的时间和空间，而且只能在适当的时期进行。为了更快但同样可靠的筛选方法，我们在体外筛选了 971 个 T-DNA 系。在幼苗和茎生无菌植物中评估了叶片发育。在温室中对新突变体进行了特征描述，以建立体外和体内叶片形态之间的关系，并揭示叶片发育与农艺性状之间可能存在的联系，这是一个有很大发现空间的有前景的领域。
对番茄 T-DNA 系进行体外筛选后，对形态发生改变的叶片的假定突变体在温室中进行了评估。在两种条件下的结果比较表明存在一般表型对应性，表明体外培养是寻找叶片发育改变的突变体的可靠系统。除了提供均匀的条件外，体外筛选的主要优点在于节省大量的时间和空间。对表型和 nptII 基因表达之间的关联进行的研究表明，在两条线中存在共分离（P > 99%）。增强子陷阱的使用还允许通过报告基因表达分析鉴定功能获得性突变体。这些研究表明，在另外三个突变体中改变的基因被 T-DNA 标记。发现了新的可能改变油菜素内酯合成或感知、决定多种表型效应的突变、影响器官曲率的突变、以及第一个具有螺旋生长的番茄突变体的突变体。结果还揭示了叶片发育与农艺性状之间的新的可能联系，如侧枝分枝、花脱落、果实发育和果实开裂。此外，我们发现突变体 2635-MM 中标记的基因编码固醇 3-β-葡萄糖基转移酶。表达分析表明，异常叶片发育可能是由于该基因的功能缺失。
体外培养是一种快速、高效和可靠的工具，可用于鉴定番茄叶片形态发生改变的突变体。在体内对新突变体的特征描述揭示了叶片发育与一些农艺性状之间的新联系。此外，还报道了一个编码固醇 3-β-葡萄糖基转移酶的基因可能参与番茄叶片发育。
