| In this paper, the cotyledons of tomato seedlings from 12 to 16 days old, which were obtained from four Chinese cultivars, were induced to produce regenerated plants by the way of organogenesis. By study on the effect of several facfors, including the concentration matching of exogenous hormones, sucrose concentration and culture condition, a stable and optimal tomato tissue culture and regeneration system of tomato was established. Also, the components and contents of the specific-stage proteins occuring in the organogenesis were analyzed preliminarily. The comparison of the protein components and contents between embryogenic and non-embryogenic calli was discussed. In this paper, the mechanisms about the tomato organogenesis, the morphochoresis of embryogenic calli and the conversion of non-embryogenic calli were first discussed. This work would make a foundation for further research in the gene regulation and molecular mechanism in the tomato organogensis.The result showed that genotype, hormone concentration, sucrose concentration and culture condition played important roles in tomato organogenesis. Only one strain of tomato (Lycopersicon escidentcen Mill.) "Jia Fen No. 10" was screened out of four cultivars for its high capacity of calli formation and rededifferentiation. Optimal calli and shoots induction medium was MS medium supplemented with 0.05mg/L IAA, l.Omg/L BA and 3% sucrose, which gave rise to a calli induction and shoot regeneration frequency of 100%.The protein components occurring in the different development stages of tomato organogenesis were compared by SDS-PAGE technique. There were different specific proteins found separately in different stages. Among them, six kinds of proteins (61KD, 54KD, 38KD, 37KD, 35KD, 23KD) were related with the morphochoresis of organs and two kinds of proteins (39KD, 24KD) were related with the morphochoresis of calli.The protein 61KD was found in the cotyledons and both the proteins 39KD and 24KD were found in embryogenic calli at different developmentstages. There were specific exppression of protein 54KD in the cotyledons, shoots and regenerated plants. Moreover, in regenerated plants, three proteins (37KD, 35KD and 23KD) were distributed in a kind specific spatial sequence. And the protein 3 8KB was found in the roots and the stem of the regenerated plants. The result suggested that there were different specific-stage proteins paticipating in rededifferentiation and developmeot during plant organogenesis, just like somatic embryogenesis.The SDS-PAGE patterns and scanning analysis showed that there was no distinctive difference hi protein components of embryogenic calli, but there were different trends of change both for the contents of protein 39KD and 24KD and for the contents of total proteins at different development stage of embryogenic callus. The reason for the results might be that the proteins of different stages had different metabolic activity. These results will provide some experimental evidences for the discussion of the plant organogenesis mechanism and the comparison of between organogenesis and somatic embryogenesis.The results obtained from the embryogenic and non-embryogenic calli indicated that these two materials were distinct in the protein components as well as contents, the pretion 54KD was detected in non-embryogenic calli not in embryogenie callus. So, the protein 54KD can be used as a molecular marker of non-embryogenic calli during tomato tissue culture.In addition, the protein contents, which included total protein contents, specific protein contents (39KD, 24KD) and non-specific protein contents (21KD, 31KD, 33KD, 36KD), in non-embryogenic calli, were lower than embryogenic calli. We supposed that the lower expression level of the proteins might be one of the important reasons that embryogenic calli lost the capacity of rededifferentiation and turned into non-embryogenic calli.Based on the results, we believed that the tomato organogenesis, the morphochoresis of embryogenic calli and the conversion of non-... |
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