Efficient regeneration and improved sonication-assisted Agrobacterium transformation (SAAT) method for Catharanthus...

Area of Science:

• Plant Biotechnology
• Medicinal Plant Research
• Molecular Biology

Background:

• Catharanthus roseus is a key medicinal plant producing over 130 bioactive compounds, including anticancer agents like vinblastine and vincristine.
• Current regeneration and genetic transformation protocols are often laborious, time-consuming, and inefficient, limiting commercial production of these valuable compounds.
• Optimizing these protocols is crucial for improving the yield and accessibility of C. roseus-derived pharmaceuticals.

Purpose of the Study:

• To develop an efficient and rapid protocol for regeneration and genetic transformation of Catharanthus roseus.
• To enhance transformation frequency and reduce the time scale for producing valuable bioactive molecules.
• To compare the efficacy of a novel sonication-assisted transformation method with conventional approaches.

Main Methods:

• Optimization of plant growth regulator concentrations (BAP and NAA) for callus and shoot regeneration from hypocotyl explants.
• Genetic transformation using Agrobacterium combined with sonication-assisted transformation (SAAT) with the pRepGFP0029 construct.
• Assessment of transformation efficiency via GFP localization in leaf tissues and confirmation of gene integration using PCR analysis.

Main Results:

• Maximal callus formation (52%) and shoot regeneration (80%) were achieved with specific concentrations of BAP and NAA.
• The SAAT method yielded a transformation efficiency of 6.0%, significantly higher than the conventional method's 3.5%.
• GFP expression was successfully localized in leaf tissues, and PCR analysis confirmed the integration of the nptII gene in transformed plantlets.

Conclusions:

• The optimized protocol using hypocotyl explants and SAAT significantly improves regeneration and genetic transformation efficiency in Catharanthus roseus.
• This enhanced efficiency facilitates increased production of important bioactive compounds, making commercialization more feasible.
• The developed method offers a faster and more effective approach for genetic manipulation of this valuable medicinal plant.