Plastid Structural Adaptations and Functional Diversity: Understanding the Link

Ayesha Faiz*1,2, Faiz Ahmad Joyia2, Sehar Nawaz2, Hafiz Mamoon Rehman2, Adeeba zafar1 and Abida Parveen1

1Department of Botany, University of Agriculture Faisalabad, Pakistan 2Centre of Agricultural Biochemistry and Biotechnology University of Agriculture Faisalabad, Pakistan

Abstract

Plastids are significant organelles found commonly in plant and algal cells for photosynthesis and other specialized functions. Chloroplasts are capable of converting light into chemical energy stored in the bonds in glucose using the chlorophyll in thylakoids and other biochemicals in stroma. These plastids are mainly green owing to the presence of chlorophyll found in grana thylakoids. During fruit ripening and other developmental processes there is changeover of chloroplasts to chromoplasts which is characterized by thylakoid degradation accompanied by chlorophyll loss while plastoglobules increase, and carotenoids get accumulated. This irreversible change is common in different vegetables and fruits. On the other hand, change from chloroplasts to gerontoplasts happens with the age therefore changing the structures and general functionality of photosynthesis. Moreover, it has been identified that elaioplasts which are the component part of lipid storage are present in different plant organs such as flowers, fruits as well as seeds. Their development is species specific and has been exemplified by studies in Arabidopsis thaliana which shows that proplastids develop into elaioplasts at a particular stage of development. This article is a systematic and detailed analysis of plastid types, their functions and their conversion, focusing on the importance of functional diversification of plastids, and its relation to plant differentiation and evolution.