Abstract:Matrix metalloproteinases (MMPs) are highly conserved zinc-dependent endopeptidases.Medicinal studies have shown that human MMPs are not only playing crucial roles in a wide range of physiological processes,but also associated with numerous serious diseases.For instance,MMPs are highly up-regulated in malignant tumor tissues and closely linked with tumor invasion and metastasis.MMPs are also widely present in higher plants and plant MMPs might be involved in several aspects such as regulation of development,plant innate immunity and responses to abiotic stresses.In this review we provide a brief introduction to the distribution,structural features,activity modulation and biological functions of plant MMPs and summarize recent progresses from the relevant studies.In addition,we discussed the research tendencies and key questions within this field.