School of Biotechnology

Madurai Kamaraj University, Madurai


Dr. R. Usha,
Department of Plant Biotechnology,
School of Biotechnology
Phone: 91-452-2458230
Email: [email protected]
           [email protected]

Publications Research Projects People

  Research Interest

  1. Molecular and structural biology of plant viruses.

  1. Saravanakumar,M., Panicker.S. & Usha.R. (1998). Partial characterization and early detection of a virus associated with necrosis disease of small cardamom in South India. Indian Journal of Virology 14 (1), 59-63.

  2. Vijayalakshmi,C. & Usha.R. (1999). Sequence analysis of movement proteins of plant viruses. Indian Journal of Virology 15(1), 15-25.

  3. Lin,T., Chen,Z., Usha.R., Stauffacher,C., Dai,J.B., Schmidt,T. & Johnson,J.E. (1999). The refined crystal structure of cowpea mosaic virus at 2.8 A resolution. Virology 265, 20-34.

  4. Sujatha,S. & Usha.R. (2000). Presence of a possible retinoblastoma protein binding motif in the AC2 protein of subgroups II and III geminiviruses. Current Science. 79 (9), 1159-1161.

  5. Jose, J. & Usha.R. (2000). Extraction of geminiviral DNA from a highly mucilaginous plant (Abelmoschus esculentus). Plant Molecular Biology Reporter 18(4), 349-355.

  6. Jacob,T. & Usha.R. (2001). 3' terminal sequence analysis of the RNA genome of the Indian isolate of cardamom mosaic virus: A new member of genus Macluravirus of Potyviridae. Virus Genes 23 (1), 81-88.

  7. Sujatha,S., Arockiasamy,A., Krishnaswamy,S. & Usha.R. (2001). Molecular Modeling of Epitope Presentation Using The Membrane Protein OmpC. Indian Journal of Biochemistry & Biophysics 38, 294-297.

  8. Jacob, T. and Usha. R (2002). Expression of Cardamom mosaic virus coat protein in Escherichia coli and its assembly into filamentous aggregates. Virus Research 86(1-2),133-141.

  9. Jose,J. and Usha.R (2003). Bhendi Yellow Vein Mosaic Disease in India Is Caused by Association of a DNA Beta Satellite with a Begomovirus. Virology 305, 310-317.

  10. Jacob, T., Jebasingh, T., Venugopal, M.N. and Usha.R. (2003). High genetic diversity in the coat protein and the 3�untranslated regions among the geographical Isolates of Cardamom mosaic virus from south India. Journal of Biosciences 28(5), 589-595.

  11. Usha. R. and Veluthambi, K. (2003). Genetic engineering for virus resistance. In Improvement Strategies for Leguminosae Biotechnology 255-268. P.K.Jaiwal and R.P.Singh (Eds.) Kluwer Academic Publishers, Great Britain.

  12. Roy, A., Savithri, H.S. and Usha.R. (2003). Spices in Virus and virus-like diseases of major crops in developing countries .Lobenstein,G. & Thottappilly, G. (Eds.) Kluwer Academic Publishers.

  13. Girish, K. R. and Usha. R. (2005). Molecular characterization of two soybean- infecting begomoviruses from India and evidence for recombination among legume-infecting begomoviruses from South-East Asia. Virus Research.108, 167-176.


Research activities:

1)      Cardamom mosaic virus: Molecular characterization has revealed that the virus is a new member of the Macluravirus genus of family Potyviridae. Sequencing of the coat protein gene of eight isolates of the virus from all over the cardamom tract of South India has shown the extensive genetic diversity of this virus.

2)      Bhendi yellow vein mosaic virus: The complete DNA A and the coat protein gene of three variants have been sequenced. A novel satellite DNA b associated with this virus has also been characterized for the first time in India. This satellite DNA has been shown to be essential for disease development.

3)      Soybean isolate of Mungbean yellow mosaic India virus and Mungbean yellow mosaic virus from Madhya Pradesh and Madurai respectively, have been completely characterized.

4)      Horsegram yellow mosaic virus from Tamil Nadu has been completely characterized.

5)      The coat protein and the RNA-dependent RNA polymerase of Cardamom mosaic virus, the coat protein, replicase and bC1 proteins of Bhendi yellow vein mosaic virus and the movement and replicase proteins of the soybean isolate of Mungbean yellow mosaic India virus have been expressed in E.coli and purified for structural studies.



Current Projects

1)      �Development of transgenic cardamom for virus resistance� funded by DBT (Part of the CPMB project).

2)      �Development of transgenic soybean with a broad-spectrum resistance to the various strains of Soybean yellow mosaic virus� funded by DBT.

Completed projects:

1)      �Molecular Characterization of Bhendi Yellow Vein Mosaic Virus, A Whitefly � Transmitted Geminivirus� funded by CSIR.

2)      �Functional Characterization of A Satellite DNA (DNA b) Associated with Bhendi Yellow Vein Mosaic Disease (BYVMD)� funded by CSIR.



PhD students (completed) and their placement records:

1)      Dr. Thomas Jacob

Research associate

Center for Biomarker Discovery (HRC-5)

Oregon Health & Science University

Portland, Oregon 97239 U.S.A.

[email protected]

2)      Dr. Joyce Jose

Post Doctoral Research Associate,

Department of Biological Sciences,915 W. State St.,

Purdue University,

West Lafayette,

Indiana47906 U.S.A.

[email protected]

3)      Mr. K. R. Girish

Submitted thesis and completed viva.

Current PhD students

1)      Mr. T. Jebasingh

2)      Mr. P. Pravin Kumar

3)      Mr. A. D. Barnabas (FIP)

4)      Mr. P. Gopal

Project fellows:

1)      Ms. C. Manohari

2)      Mr. A. Kasin Yadunandam


Ms. R. M. Packialakshmi

Ms. Shanthini Devi

Lab assistant:

Mr. E. Sundaram