title: Structure and dynamics of Antarctic fish neuroglobin assessed by computer simulations.
abstract: Neuroglobin (Ngb) is a heme protein, highly conserved along evolution, predominantly found in the nervous system. It is upregulated by hypoxia and ischemia and may have a neuroprotective role under hypoxic stress. Although many other roles have been proposed, the physiological function is still unclear. Antarctic icefishes lack hemoglobin and some species also lack myoglobin, but all have Ngb and thus may help the elucidation of Ngb function. We present the first theoretically derived structure of fish Ngb and describe its behavior using molecular dynamics simulations. Specifically, we sequenced and analyzed Ngbs from a colorless-blooded Antarctic icefish species Chaenocephalus aceratus and a related red-blooded species (Dissostichus mawsoni). Both fish Ngbs are 6-coordinated but have some peculiarities that differentiate them from mammalian counterparts: they have extensions in the N and C termini that can interact with the EF loop, and a gap in the alignment that changes the CD-region structure/dynamics that has been found to play a key role in human neuroglobin. Our results suggest that a single mutation between both fish Ngbs is responsible for significant difference in the behavior of the proteins. The functional role of these characteristics is discussed.
authors: Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad de Buenos Aires, Argentina.
authors: Ignacio
authors: I
authors: Boron
authors: Roberta
authors: R
authors: Russo
authors: Leonardo
authors: L
authors: Boechi
authors: C-H Christina
authors: CH
authors: Cheng
authors: Guido
authors: G
authors: di Prisco
authors: Darío A
authors: DA
authors: Estrin
authors: Cinzia
authors: C
authors: Verde
authors: Alejandro D
authors: AD
authors: Nadra
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000864:Antarctic Regions; D001483:Base Sequence; D003198:Computer Simulation; D017931:DNA Primers; D005399:Fishes; D005914:Globins / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry*; D000078787:Neuroglobin; D017386:Sequence Homology, Amino Acid
chemical_list: D017931:DNA Primers; D009419:Nerve Tissue Proteins; D000078787:Neuroglobin; D005914:Globins