Jawahar Singh, Ph.D.

Engineering how plants make their own fertilizer.

Postdoctoral Research Associate

Sainsbury Laboratory, University of Cambridge

ENSA Root Nodule Symbiosis CRISPR Engineering
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Dr. Jawahar Singh
35+ Publications
3 Countries
4 Crop Species
10+ Students Mentored

Research Highlights

Key discoveries at the intersection of nutrient signalling and symbiosis

Phosphate–Nodulation Nexus

First Discovery

Singh et al. 2025

First report that a PHR transcription factor directly regulates the master nodulation gene NIN — demonstrating that phosphate availability gates whether a legume commits to forming nitrogen-fixing nodules. This discovery opens an entirely new regulatory axis in symbiosis research.

Adequate Pi: SPX sequesters PHR-L7 and NIN is expressed, enabling symbiosis. Low Pi: PHR-L7 is active, NIN is repressed, no symbiosis.
Under adequate phosphate, SPX sequesters PHR-L7 (inactive) and NIN is expressed, enabling symbiosis. Under low Pi, PHR-L7 becomes active, represses NIN, and nodulation is blocked.

From phenotype to direct DNA binding

PvPHR-L7 RNAi increases, and over-expression decreases, nodulation in P. vulgaris (Singh et al. 2025, Fig. 1A-B)
Fig. 1 — PvPHR-L7 RNAi increases nodulation; over-expression decreases nodulation in P. vulgaris.
EMSA: recombinant PvPHR-L7 binds P1BS motifs in PvNIN and PvTML promoters (Singh et al. 2025, Fig. 5)
Fig. 2 — Recombinant PvPHR-L7 binds the P1BS cis-element in PvNIN and PvTML promoters (EMSA).
Transactivation: PvPHR-L7 activates pPvNIN:GUS and pPvTML:GUS in N. benthamiana leaves (Singh et al. 2025, Fig. S8)
Fig. 3 — PvPHR-L7 transactivates PvNIN and PvTML in N. benthamiana leaves (RT-qPCR and GUS staining).

Phosphate is not just a nutrient — it is a gatekeeper that determines whether legumes commit to nitrogen-fixing symbiosis

PHR-L7 · NIN promoter · 2025 Read Paper →

CRISPR Engineering for N-Fixation

Ongoing at Cambridge

Investigating legume nodule symbiosis in Dr. Sebastian Schornack's group at the Sainsbury Laboratory. Studying conserved negative regulators of nitrogen fixation in crop legumes — cowpea and soybean — and using CRISPR-Cas9 knockouts and promoter fine-tuning to improve nitrogen fixation and field performance.

ENSA →

Selected Publications

First and corresponding author publications shaping the field

2026

Singh, J., Valdés-López, O., & Schornack, S.

Beyond Nitrogen: Phosphate Controls Root Nodule Symbiosis Commitment

Perspective article defining the phosphate-nodulation paradigm

doi.org/10.1016/j.tplants.2026.01.001

2025

Singh, J., Mendoza-Soto, A. B., Tiwari, M., et al.

Phosphate deficiency reduces nodule formation through a phosphate starvation response-like protein in Phaseolus vulgaris

First evidence of PHR1 directly binding the NIN promoter

doi.org/10.1093/pcp/pcaf069

2023

Singh, J., Isidra-Arellano, M.C., & Valdés-López, O.

Harnessing the potential of symbiotic associations of plants in phosphate-deficient soil for sustainable agriculture

Review on symbiotic strategies for phosphate-poor soils

doi.org/10.1093/pcp/pcad059

2023

Singh, J. & Verma, P. K.

Role of Nod factor receptors and its allies involved in nitrogen fixation

Review on Nod factor receptor signalling

doi.org/10.1007/s00425-023-04090-7

2023

Singh, J. & Valdés-López, O.

Discovering the genetic modules controlling root nodule symbiosis under abiotic stresses: salinity as a case study

Framework for understanding symbiosis under environmental stress

doi.org/10.1111/nph.18627

2022

Singh, J. & Verma, P. K.

Genome-wide identification, expression, and characterization of CaLysM-RLKs in chickpea root nodule symbiosis

Identified 17 LysM-RLKs governing Nod factor perception in chickpea

doi.org/10.1016/j.envexpbot.2022.104999

+ 7 editorials at MPMI, 8 book chapters, and additional co-authored publications

View Full Publication List → Google Scholar

About

Background and research trajectory across India, Mexico, and the UK

I am a plant molecular biologist driven by a single question: how do legumes decide when and where to form nitrogen-fixing root nodules? This decision integrates nutrient signals, developmental cues, and microbial dialogues — and understanding it holds the key to reducing agriculture's dependence on synthetic fertilizers.

My research journey has taken me from studying salt-stressed millets in the Thar Desert (India), to dissecting Nod factor signalling in chickpea (New Delhi), to discovering how phosphate controls nodulation commitment in common bean (Mexico), and now to CRISPR-engineering enhanced nitrogen fixation in cowpea and soybean at Cambridge. Each step has built a unique, integrative perspective on legume symbiosis.

I am an Assistant Feature Editor at Molecular Plant-Microbe Interactions (MPMI) and co-organized the satellite meeting on mentoring at IS-MPMI Congress 2025 in Cologne, reflecting my commitment to both science communication and community building.

2023–Present

Sainsbury Laboratory, University of Cambridge, UK

Postdoctoral Research Associate with Prof. Sebastian Schornack (ENSA) — CRISPR-engineering cowpea and soybean for enhanced nitrogen fixation. Functional genomics dissection of nodule development.

2022–2023

UNAM, Mexico City, Mexico

DGAPA Postdoctoral Fellow with Prof. Oswaldo Valdés-López — First to demonstrate that PHR1 directly binds the NIN promoter, linking phosphate availability to the master switch of nodulation.

2016–2022

NIPGR, New Delhi, India

Ph.D. in Plant Biology with Prof. Praveen K. Verma — Discovered 17 LysM receptor-like kinases for Nod factor perception in chickpea. Identified MAP kinases as critical signal transducers from membrane to nucleus.

2015–2016

JNVU, Jodhpur, India

Research Fellow with Prof. Shweta Jha — Stress proteomics in pearl millet. Identified salt-responsive proteins and physiological markers for stress tolerance breeding.

2012–2014

West Bengal State University, Kolkata, India

M.Sc. in Biochemistry — Foundational training in protein biochemistry, enzymology, and molecular biology, sparking a long-term interest in how nutrients and signalling molecules shape plant physiology.

Future Lab Vision

Engineering nutrient-smart symbiosis for sustainable agriculture

My independent research program will decode the cell-type specific nutrient signalling logic of nodulation and rewire it using genome engineering to create climate-resilient, low-fertilizer legume varieties for global agriculture.

01

Decoding Nutrient Crosstalk During Nodulation

Mapping how nitrogen, phosphorus, potassium, and iron signals converge on nodulation decisions, using a combination of transcriptomic, epigenomic, and proteomic approaches across multiple legume species.

Multi-omics integration Regulatory networks
02

Engineering Nutrient Transporters

Integrating proteomics with transcriptomics to identify and functionally characterize nutrient transporters in nodules. Creating CRISPR knockout and overexpression lines with synthetic nutrient-responsive promoters.

CRISPR-Cas9 Transporter biology
03

Synthetic Rewiring of Signalling Pathways

Assembling synthetic transcriptional circuits combining elements from nitrate, phosphate, and potassium signalling pathways. Multiplex CRISPR editing to reprogram multiple regulatory pathways simultaneously.

Synthetic biology Golden Gate cloning
04

Field Validation & Farmer Impact

Evaluating engineered varieties in nutrient-poor and saline soils. Participatory field trials with smallholder farmers in South Asia and sub-Saharan Africa. Technology transfer through agricultural extension partnerships.

Translational research Food security

Let's Collaborate

I am always open to scientific discussions, collaborations, and new ideas at the intersection of nutrient signalling, symbiosis, and crop engineering. Whether you are working on legume biology, genome editing, or sustainable agriculture — let's connect and explore synergies.

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Teaching & Mentoring

Cultivating the next generation of plant scientists

Teaching at Cambridge

Undergraduate supervisor for the Plant and Microbial Sciences (IBPMS) course, covering topics including Feeding the World, Pathological and Beneficial Plant-Microbe Interactions. Conducted revision sessions and guided students in essay writing, critical analysis, and interpretation of research data.

Research Mentoring

Mentored multiple Master's research students and summer interns at Cambridge on root nodule development and molecular regulation of symbiosis. Provided hands-on training in molecular biology, confocal imaging, CRISPR techniques, and data analysis.

Courses I Can Offer

  • Molecular Plant-Microbe Interactions
  • Genetic Engineering & Biotechnology
  • Cell Signaling & Stress Biology
  • Plant Physiology
  • Advanced Cell Biology
  • Techniques in Modern Biology

Proposed New Courses

  • Molecular Dialogues in the Rhizosphere
  • Symbiotic Signalling in Sustainable Agriculture
  • Biotic & Abiotic Stress Tolerance in Plants
  • Advanced Topics in Plant Symbiosis & Nutrient Acquisition

Leadership & Service

Building community in plant-microbe interactions research

Assistant Feature Editor

Molecular Plant-Microbe Interactions (MPMI), 2024–Present. Contributing science communication through accessible summaries, author interviews, and commentaries.

Conference Organizer

Co-organizer & Chair of satellite meeting "Building Careers in MPMI through Effective Mentoring" at IS-MPMI Congress 2025, Cologne. Poster judge for Best Poster Award. Mini-symposium co-organizer at Sainsbury Laboratory.

Peer Reviewer

Reviewer for The Plant Cell, New Phytologist, The Plant Journal, Journal of Experimental Botany, Frontiers in Plant Science, BMC Plant Biology, and Scientific Reports.

Awards & Fellowships

DGAPA Postdoctoral Fellowship (UNAM, Mexico). CSIR-UGC Senior & Junior Research Fellowships (India). GATE qualified. Swachhta Saarthi Fellowship (Govt. of India).

Get in Touch

Open to PI opportunities, collaborations, and seminar invitations worldwide

Address

Sainsbury Laboratory
University of Cambridge
47 Bateman Street
Cambridge CB2 1LR, UK