ABSTRACT
In recent years, gene engineering is developing rapidly and many recombinant proteins have been expressed. The use of plant bioreactor to express specific pharmaceutical proteins provides a new way for the prevention and treatment of some important diseases in human beings. Nowadays, chloroplast genetic transformation and expression system has become a research hotspot in plant bioreactor. Higher plant chloroplasts have unique advantages in the expression of recombinant proteins due to their special structures and inherited characteristics: such as high expression, site-specific integration, and the maternal inheritance characteristics of exogenous genes. The maternal inheritance of chloroplast is helpful for biological safety of transgene escaping by pollens. Many important pharmaceutical proteins have been successfully expressed in plant chloroplasts. As a chloroplast transformation model of higher plants, tobacco has made significant progress in the expression of pharmaceutical proteins, such as vaccine antigens, antibodies, and other important recombinant proteins. Chloroplast genetic transformation in higher plants also provides new techniques and methods for the study of chloroplast gene expression and regulation mechanisms. In order to provide a new idea for the development of chloroplast expression platform and the expression of important pharmaceutical proteins, this review outlined the progress of chloroplast genetic transformation system in higher plants, including the chloroplast transformation principle, vector construction, expression of recombinant proteins and important pharmaceutical proteins, and the effects of recombinant proteins expression on plant metabolism and traits.