Solution structure of the ubiquitin-like domain of human DC-UbP from dendritic cells.
The previously identified dendritic cell-derived ubiquitin-like protein (DC-UbP) was implicated in cellular differentiation and apoptosis. Sequence alignment suggested that it contains a ubiquitin-like (UbL) domain in the C terminus. Here, we present the solution NMR structure and backbone dynamics of the UbL domain of DC-UbP. The overall structure of the domain is very similar to that of Ub despite low similarity (<30%) in amino-acid sequence. One distinct feature of the domain structure is its highly positively charged surface that is different from the corresponding surfaces of the well-known UbL modifiers, Ub, NEDD8, and SUMO-1. The key amino-acid residues responsible for guiding polyubiquitinated proteins to proteasome degradation in Ub are not conserved in the UbL domain. This implies that the UbL domain of DC-UbP may have its own specific interaction partners with other yet unknown cellular functions related to the Ub pathway.
Gao
Yong-Guang
YG
Key Laboratory of Proteomics, Institute of Biochemsitry and Cell Biology, Shanghai Institutes for Biological Sciences, Shanghai 200031, People's Republic of China.
Song
Ai-Xin
AX
Shi
Yan-Hong
YH
Chang
Yong-Gang
YG
Liu
Shu-Xun
SX
Yu
Yi-Zi
YZ
Cao
Xue-Tao
XT
Lin
Dong-Hai
DH
Hu
Hong-Yu
HY
D000595:Amino Acid Sequence; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D012996:Solutions; D055672:Static Electricity; D025801:Ubiquitin / Q000737:chemistry; D014452:Ubiquitins / Q000737:chemistry*
D009419:Nerve Tissue Proteins; D012996:Solutions; C471042:UBTD2 protein, human; D025801:Ubiquitin; D014452:Ubiquitins