Ultrastructural and Physiological Characterization of YELP, a Novel, Yellow, Chlorophyll-Deficient Cell Mutant Line That Develops Etioplast-Like Plastids in the Light

Abstract

In this work, we present an ultrastructural and physiological description of a novel chlorophylldeficient, yellow cell line of the grass Bouteloua gracilis that develops etioplast-like plastids in presence of light (YELP). These mutant cells were compared to the parental, wild-type, highly chlorophyllous cells from which they were isolated. Growth analysis, based on fresh and dry weights, indicated that YELP accumulates biomass at a slower rate than the parental, green cells. Besides, YELP developed very low levels of photosynthetic pigments, reaching only 9.3% and 38.4% of chlorophyll a and chlorophyll b, respectively, developed by the wild-type cells. Likewise, the accessory pigments, carotenes and xanthophylls, were only synthesized at 8.0% and 5.4%, respectively, of the levels reached by the green cells. Electron microscopy revealed remarkable differences in plastid ultrastructure between the wild-type and mutant cells. Plastids of YELP were heterogeneous and smaller than those found in wild-type cells. YELP plastids were abnormal with poorly developed membrane systems that prevented the accumulation of chlorophyll and accessory pigments in the mutant cell line. We expect this novel, mutant cell line will provide new tools for studying plastid development and differentiation.

RNA-Seq, co-expression network and eQTL analysis identify key genes for chlorophyll and carbon metabolism in rice

“…These mutations are classi ed based on the color of seedlings, such as greenrevertible albino, albino, zebra, etiolated, white-emerald, yellow-green, yellow, viridis, virido-albino, striata, xantha, striped, and so on [18][19][20] . Leaf color mutations are diverse and dynamic, but they all involve changes in genes involved in photosynthetic pigment metabolism, chloroplast development 4 , protein transport into the chloroplast 21 , and photosynthetic membrane proteins 22 . As a result of the identi cation of signi cant chlorophyll mutants and the mapping of genes linked to these mutations, convincing advances have been made in recent years in understanding the underlying mechanisms of various gene interactions and their involvement in the metabolism of photosynthetic pigments [23][24][25] .…”