Nam Hai CHUA, Ph.D.
Temasek Senior Investigator (Emeritus)

Professor Chua is Temasek Senior Investigator (Emeritus), Temasek Life Sciences Laboratory (TLL) and Distinguished Visiting Professor, Biochemistry Department, National University of Singapore. Also a Fellow of the UK Royal Society, an Academician of Taiwan’s Academia Sinica, and a Foreign Academician of the Chinese Academy of Sciences, China, Professor Chua has advised government organisations, institutions and MNCs worldwide, including Monsanto, DUPONT, Sumitomo Chemical Corporation, and biotechnology-related entities. He received his B.Sc. from University of Singapore; A.M. and Ph.D from Harvard University; and an honorary doctorate from Nanyang Technological University (NTU).

 

You may wish to contact Prof CHUA Nam Hai at:

Tel: +1 (212) 327-8126
Email: chua@mail.rockefeller.edu

For information on PhD studies at TLL, click HERE

 

Research Interests

• Role of lncRNA in plant abiotic/ biotic stress responses
• H₂O₂ and Ca²⁺ waves in Systemic acquired acclimation (SAA)
• Disruptive & Sustainable Technologies for Agricultural Precision (DiSTAP)

As sessile organisms, plants are not able to uproot themselves when confronted with harsh environmental conditions. Instead they develop intricate mechanisms to sense and adapt to their changing physical environments such as nutrition availability, heat, and pathogens. This form of adaptation is broadly known as abiotic/biotic stress responses.

Our lab is focused on studying plant responses to abiotic and biotic stresses using Arabidopsis thaliana as a model organism through two strategies. First, we are interested in elucidating the regulatory roles of lncRNAs in stress responses. We use molecular, biochemical, genetics and transgenic approaches including the highly controllable XVE inducible system.

Second, we are developing new tools to study Systemic Acquired Acclimation (SAA) in plants by the accurate measurement of H₂O₂ and Ca²⁺ions spatially and temporally. The novel tools will be used in conjunction with transgenic plants to elucidate the signaling transduction mechanism of SAA.

Knowledge generated from our lab will be relevant and can be applied to biotechnological improvement of commercial crops.

lncRNA and abiotic stress responses We have recently characterized that the Arabidopsis genome encodes around 8,000 long intergenic noncoding RNAs (lincRNAs) and 36,000 natural antisense transcripts (NATs). There is emerging evidence demonstrating the involvement of lncRNA in various developmental events and stress responses. At present, we focus our attention on the role of these lncRNAs in nutrition starvation and heat stress responses.

Nutrient starvation response Nitrates and inorganic phosphate (Pi) are limiting macronutrients for plant growth and are usually derived from fertilizers. However, intensive application of chemical fertilizer has huge ecological footprint and impact. To mitigate these concerns, we are studying the importance of lncRNAs in phosphate sensing and homeostasis.

Heat stress response Increasing global temperatures have resulted in extreme weather patterns including extreme high temperature (heat waves) that can lead to devasting crop losses. We have identified several heat stress-inducible lncRNAs from Arabidopsis transcriptomics analysis. We are investigating the function of these lncRNAs in heat stress responses and heat stress memory establishment.

LncRNA and biotic stress responses Plants that are challenged with bacteria and virus exhibit biotic stress responses. Recently, we have demonstrated the expression of ELF18-INDUCED LONG NONCODING RNA1 (ELENA1) playing regulatory roles in pathogen resistance. We showed that ELENA1 knock-down plants are more susceptible to pathogens.

We are also interested in virus satellite RNA, a form of lncRNA and virus induced noncoding RNA (vincRNA). vincRNAs are plant derived ncRNA that are expressed during virus infection. Their roles in virus defense mechanisms are being identified.

Disruptive & Sustainable Technologies for Agricultural Precision (DiSTAP)

Plants are able to propagate signal from site of perception (local leaf) to other parts of the plant (systemic leaves) to trigger gene expression to enhance plant’s adaptation to abiotic stress. This form of adaptation is known as Systemic Acquired Acclimation (SAA). SAA is found to be established by H₂O₂, Ca²⁺ and electrical waves. However, the establishment of SAA specific to various abiotic stress remains to be elucidated.

As part of the Singapore-MIT Alliance for Research and Technology (SMART) collaboration, we are currently applying nanosensors developed by the Strano Lab (MIT) to Arabidopsis to accurately measure H₂O₂ and Ca²⁺ waves temporally and spatially. Through the characterization of H₂O₂ and Ca²⁺ waves after exposure to different biotic and abiotic stress, we aim to uncover specific wave patterns corresponding to each type of SAA establishment. In collaboration with the Ram lab (MIT) we are using Raman spectroscopy to characterize and profile Arabidopsis plants that have experienced biotic or abiotic stresses but have not yet displayed symptoms.