AtECB1/MRL7, a thioredoxin-like fold protein with disulfide reductase activity, regulates chloroplast gene expression and chloroplast biogenesis in Arabidopsis thaliana.

Plastid-encoded RNA polymerase (PEP) is closely associated with numerous factors to form PEP complex for plastid gene expression and chloroplast development. However, it is not clear how PEP complex are regulated in chloroplast. Here, one thioredoxin-like fold protein, Arabidopsis early chloroplast biogenesis 1 (AtECB1), an allele of MRL7, was identified to regulate PEP function and chloroplast biogenesis.

Inhibition of DNA-dependent protein kinase catalytic subunit by small molecule inhibitor NU7026 sensitizes human leukemic K562 cells to benzene metabolite-induced apoptosis.

Benzene is an established leukotoxin and leukemogen in humans. We have previously reported that exposure of workers to benzene and to benzene metabolite hydroquinone in cultured cells induced DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to mediate the cellular response to DNA double strand break (DSB) caused by DNA-damaging metabolites. In this study, we used a new, small molecule, a selective inhibitor of DNA-PKcs, 2-(morpholin-4-yl)-benzo[h]chomen-4-one (NU7026), as a probe to analyze the molecular events and pathways in hydroquinone-induced DNA DSB repair and apoptosis.

The GDC1 gene encodes a novel ankyrin domain-containing protein that is essential for grana formation in Arabidopsis.

In land-plant chloroplasts, the grana play multiple roles in photosynthesis, including the potential increase of photosynthetic capacity in light and enhancement of photochemical efficiency in shade. However, the molecular mechanisms of grana formation remain elusive. Here, we report a novel gene, Grana-Deficient Chloroplast1 (GDC1), required for chloroplast grana formation in Arabidopsis (Arabidopsis thaliana).

[Genetic mapping of rice gene OsALB23 regulating chloroplast development].

The biogenesis of chloroplast from proplastid is the prerequisite of photosynthesis. Using electron microscope, we found that rice albino mutant Osalb23 had no thylakoid inside the chloroplast, only some empty vesicles could be observed (Fig. 2).