Got Chlorophyll? The Investigation of Two Chlorophyll-Deficient Mutants in Soybean
Mentor 1
Dr. Devinder Sandhu
Location
Union 240B
Start Date
24-4-2015 9:00 AM
Description
Chlorophyll-deficient mutants have been studied in several plant species. We have identified a lethal-yellow and a viable-yellow mutant in soybean. In comparison to green plants, the lethal-yellow and viable-yellow plants showed significant reduction of Chlorophyll A and B. Photochemical conversion efficiency was reduced in the viable-yellow plants, whereas, lethal-yellow plants showed no ability to convert light energy. The three phenotypes, green, lethal-yellow, and viable-yellow were easily distinguished based on their light reflectance indices. A reduction in thylakoid stacking was apparent in the viable-yellow plants. In the lethal-yellow genotypes, proplastids did not differentiate into chloroplasts and contained very few membranes. Genetic analysis revealed recessive epistatic interaction between the lethal- and viable-yellow genes. The lethal-yellow gene was mapped to a 347 kb region on chromosome 3 that contained 45 predicted genes. The viable-yellow gene was mapped to a 227 kb region on chromosome 2. We located 24 predicted genes in the region. Of these, one candidate gene is of particular interest, as it showed homology to a translocon in the inner membrane of chloroplast (Tic110) in Arabidopsis. Tic110 is known to play critical role in plastid biogenesis and heterozygous mutants for Tic110 in Arabidopsis exhibited a pale phenotype. Characterization of lethal-yellow and viable-yellow genes may help to better understand the biosynthetic pathways involved in the development of chloroplasts.
Got Chlorophyll? The Investigation of Two Chlorophyll-Deficient Mutants in Soybean
Union 240B
Chlorophyll-deficient mutants have been studied in several plant species. We have identified a lethal-yellow and a viable-yellow mutant in soybean. In comparison to green plants, the lethal-yellow and viable-yellow plants showed significant reduction of Chlorophyll A and B. Photochemical conversion efficiency was reduced in the viable-yellow plants, whereas, lethal-yellow plants showed no ability to convert light energy. The three phenotypes, green, lethal-yellow, and viable-yellow were easily distinguished based on their light reflectance indices. A reduction in thylakoid stacking was apparent in the viable-yellow plants. In the lethal-yellow genotypes, proplastids did not differentiate into chloroplasts and contained very few membranes. Genetic analysis revealed recessive epistatic interaction between the lethal- and viable-yellow genes. The lethal-yellow gene was mapped to a 347 kb region on chromosome 3 that contained 45 predicted genes. The viable-yellow gene was mapped to a 227 kb region on chromosome 2. We located 24 predicted genes in the region. Of these, one candidate gene is of particular interest, as it showed homology to a translocon in the inner membrane of chloroplast (Tic110) in Arabidopsis. Tic110 is known to play critical role in plastid biogenesis and heterozygous mutants for Tic110 in Arabidopsis exhibited a pale phenotype. Characterization of lethal-yellow and viable-yellow genes may help to better understand the biosynthetic pathways involved in the development of chloroplasts.
