InterPro domain: IPR044701

This family represents a group of plant thioredoxin-like fold domain-containing proteins, including MRL7 (Protein MESOPHYLL-CELL RNAI LIBRARY LINE 7, also known as Protein EARLY CHLOROPLAST BIOGENESIS 1 (ECB1) or Protein SUPPRESSOR OF VARIEGATION 4 SVR4) and its paralog MRL7L from Arabidopsis. These proteins are required for early chloroplast development and involved in the regulation of plastid gene expression [ 1 , 2 , 3 , 4 , 5 ]. They also mediate the degradation of two repressors of chloroplast biogenesis, PIF1 and PIF3 in nucleus [ 6 ]. MRL7L is a necessary component of phytochrome signalling for photosynthesis-associated plastid-encoded genes (PhAPGs) activation [ 7 ].

1. SUPPRESSOR OF VARIEGATION4, a new var2 suppressor locus, encodes a pioneer protein that is required for chloroplast biogenesis. Mol Plant 4, 229-40
2. Two novel proteins, MRL7 and its paralog MRL7-L, have essential but functionally distinct roles in chloroplast development and are involved in plastid gene expression regulation in Arabidopsis. Plant Cell Physiol 52, 1017-30
3. AtECB1/MRL7, a thioredoxin-like fold protein with disulfide reductase activity, regulates chloroplast gene expression and chloroplast biogenesis in Arabidopsis thaliana. Mol Plant 7, 206-17
4. SVR4 (suppressor of variegation 4) and SVR4-like: two proteins with a role in proper organization of the chloroplast genetic machinery. Physiol Plant 150, 477-92
5. PRDA1, a novel chloroplast nucleoid protein, is required for early chloroplast development and is involved in the regulation of plastid gene expression in Arabidopsis. Plant Cell Physiol. 54, 2071-84
6. NCP activates chloroplast transcription by controlling phytochrome-dependent dual nuclear and plastidial switches. Nat Commun 10, 2630