Phytochelatins and Cadmium Mitigation: Harnessing Genetic Avenues for Plant Functional Manipulation

Abstract

Among the highly toxic heavy metals, cadmium (Cd) is highlighted as a persistent environmental pollutant, posing serious threats to plants and broader ecological systems. Phytochelatins (PCs), which are synthesized by phytochelatin synthase (PCS), are peptides that play a central role in Cd mitigation through metal chelation and vacuolar sequestration upon formation of Cd-PC complexes. PC synthesis interacts with other cellular mechanisms to shape detoxification outcomes, broadening the functional scope of PCs beyond classical stress responses. Plant Cd-related processes have has been extensively investigated within this context. This perspective article presents key highlights of the panorama concerning strategies targeting the PC pathway and PC synthesis to manipulate Cd-exposed plants. It discusses multiple advances on the topic related to genetic manipulation, including the use of mutants and transgenics, which also covers gene overexpression, PCS-deficient and PCS-overexpressing plants, and synthetic PC analogs. A complementary bibliometric analysis reveals emerging trends and reinforces the need for interdisciplinary integration and precision in genetic engineering. Future directions include the design of multigene circuits and grafting-based innovations to optimize Cd sequestration and regulate its accumulation in plant tissues, supporting both phytoremediation efforts and food safety in contaminated agricultural environments.

Keywords: abiotic stress; cadmium; genetic engineering; heavy metals; phytochelatin; phytochelatin synthase; plant biotechnology; tolerance; transgenics.

Figure 1

Overview of PC-related Cd mitigation research in plants employing genetic manipulation strategies.

Figure 2

Flowchart for searching and filtering articles on ‘phytochelatins’ and ‘cadmium’ in plants, focusing on studies with ‘mutants’ and ‘transgenics’. * Indicates inclusion and selection criteria used during filtering process.

Figure 3

Bibliometric analysis of global participation and research collaboration networks by country (A), institutions (B), authors (C) and keyword co-occurrence network (D) in articles on ‘phytochelatins’ and ‘cadmium’ in plants, focusing on studies with ‘mutants’. The size of the circles represents the volume of publications or the frequency of keywords, while the thickness of the lines indicates the strength of the connections or collaborations between the elements analyzed.

Figure 4

Bibliometric analysis of global participation and research collaboration networks by country (A), institutions (B), authors (C), and keyword co-occurrence network (D) in articles on ‘phytochelatins’ and ‘cadmium’ in plants, focusing on studies with ‘transgenics’. The size of the circles represents the volume of publications or the frequency of keywords, while the thickness of the lines indicates the strength of the connections or collaborations between the elements analyzed.