My research so far has focused on understanding the molecular basis of plant developmental switches and the mechanisms underlying reprogramming differentiated cells into embryonic stem cells. The topics to be addressed include plant ageing, rejuvenation, life history strategy, secondary growth, embryogenesis, cell biology, live-cell imaging, chromatin organization, auxin signaling, chemical biology, and in vitro regeneration.
Somatic embryogenesis is a unique biological process in which differentiated somatic cells acquire the ability to induce an embryo and regenerate an entire plant. The mechanisms drive acquiring of embryotic traits in somatic cells is a fundamental question in plant biology. Apart from being a tool to study and understanding embryogenesis, the somatic embryogenesis is an important clonal propagation tool used by all major seed companies, where it is used to facilitate the breeding process, to propagate parental lines for hybrid seed production, and to propagate highly heterozygous or open-pollinated varieties that are sold as plantlets.
Plant growth regulators, in particular the synthetic auxin and herbicide 2,4-D, are potent inducers of embryonic stem cells. The positive relationship between stress and induction of embryonic stem cells also is well documented. Currently, we have combined molecular biology, cell biology and organic chemistry approaches to answer this question, how do stress and auxin converge to induce plant cell totipotency.
Plant ageing and life history strategy
The genetic characteristics of the process of ageing and life history strategy in plants is a timely research topic. Many flowering plant species are monocarpic. Monocarpic plants produce seed but are unable to grow further. By contrast, many other flowering plant species are polycarpic. Polycarpic plants generally live for more than two growing seasons and do so by maintaining meristems in the vegetative state, allowing them to produce new shoots after seed set. The molecular base that differentiates between seed set-linked death in monocarpic plants and survival of polycarpic plants even after multiple rounds of flowering and seed set are still largely unknown.
Currently, I am involved with the project "plant ageing and life history strategy". This research project aims to identify key regulators that control the aging process in plants.
Karami, O., Rahimi, A., Khan, M., Bemer, M., Hazarika, R.R., Mak, P., Compier, M., van Noort., V. & Offringa, R. (2020) A suppressor of axillary meristem maturation promotes longevity in flowering plants. Nature Plants, 6, 368–376
Karami, O., & Saidi, A. (2010). The molecular basis for stress-induced acquisition of somatic embryogenesis. Molecular Biology Reports, 37(5), 2493-2507.
Karami, O., Deljou, A., & Kordestani, G. K. (2008). Secondary somatic embryogenesis of carnation (Dianthus caryophyllus L.). Plant Cell, Tissue and Organ Culture, 92(3), 273-280
No relevant ancillary activities