LAUSR

Developmental genes (DG)/ morphogenic genes are involved in enhancing the transformation and regeneration of plants. One such DG is the WUSCHEL (WUS) gene, a homeodomain transcription factor, and is involved in the stem cell maintenance of shoot apical meristem (SAM). In dicots, ectopic expression of WUS induced the embryogenic calli formation and organogenesis. On the other, WUS overexpression resulted in pleiotropic effects in most of the monocots. Also, very few dicots failed to regenerate due to the overexpression of WUS. In our study, the 35S driven WUS (AtWUS) gene expressing transgenic rice plants were generated. All the transgenic plants with the WUS (W) gene along with the vector (V) and untransformed (U) lines were confirmed by detailed Southern analyses. The single-copy W and V plants with complete T-DNA were taken for detailed analyses. The W plants exhibited few phenotypic changes such as thick stem, reduction in the internode length, enclosed panicle, unopen flower, pale yellow colour of the anther, and loss of viable pollens compared to the U and V plants. Interestingly, crown root formation and small vein formation in the leaves were detected in the W plants. The expression of the WUS gene was confirmed by RT-PCR analysis in the W plants. The seeds from the hemizygous plants showed enhanced embryogenic calli formation and attained early regeneration compared to U and V plants thereby confirming the role of the WUS gene in embryogenesis and regeneration.