Fig. 3
From: Lignin engineering through laccase modification: a promising field for energy plant improvement
Sequence and structure of AtLAC4 from A. thalina. a The amino acid sequence of AtLAC4. The protein consists of 558 amino acids and weighs 61.5 kDa, with theoretical pI value of 9.31. It has a signal peptide (underlined) at the N-terminal predicted by SignalP 4.1 Server [98] and three conserved Cu-oxidase domains (colored in red, blue and green, respectively), according to Pfam [99]. Twelve asparagines predicted to be N-glycosylated by NetNGlyc 1.0 Server [100] were indicated in bold. b MiR397a mediated cleavage of AtLAC4, adapted from Abdel-Ghany et al. [63]. The black boxes represent exons and the horizontal lines represent introns. The white box represents 5′-UTR, while the white arrow represents 3′-UTR. Vertical arrow indicates the 5′ termini of miRNA-guided cleavage products, with the frequency of clones shown. Watson–Crick pairing (solid lines) and G:U wobble pairing (ellipse) between AtLAC4 target sequence and the complementary miRNA397a sequence are indicated. c The view of ligands at the copper center of AtLAC4. Cu1 is coordinated with two histidines, one cysteine and one leucine, Cu2 is coordinated by another two histidines and one H2O ligand, while six histidines coordinate the Cu3 pair in a symmetrical manner, with a bridging OH ligand. d Three-dimensional structure of AtLAC4 predicted by SWISS-MODEL [101]