Charge-neutralization effect of the tail regions on the histone H2A/H2B dimer structure.
It is well known that various modifications of histone tails play important roles in the regulation of transcription initiation. In this study, some lysine (Lys) and arginine (Arg) residues were acetylated and deiminated, respectively, in the histone H2A/H2B dimer, and charge-neutralization effects on the dimer structure were studied by native mass spectrometry. Given that both acetylation and deimination neutralize the positive charges of basic amino acid residues, it had been expected that these modifications would correspondingly affect the gas-phase behavior of the histone H2A/H2B dimer. Contrary to this expectation, it was found that Arg deimination led to greater difficulty of dissociation of the dimer by gas-phase collision, whereas acetylation of Lys residues did not cause such a drastic change in the dimer stability. In contrast, ion mobility-mass spectrometry (IM-MS) experiments showed that arrival times in the mobility cell both of acetylated and of deiminated dimer ions changed little from those of the unmodified dimer ions, indicating that the sizes of the dimer ions did not change by modification. Charge neutralization of Arg, basicity of which is higher than Lys, might have triggered some alteration of the dimer structure that cannot be found in IM-MS but can be detected by collision in the gas phase.
Department of Medical Life Science, Graduate School of Medical Life Science, Yokohama City University, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
Kazumi
K
Saikusa
Department of Medical Life Science, Graduate School of Medical Life Science, Yokohama City University, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
Singo
S
Shimoyama
Department of Medical Life Science, Graduate School of Medical Life Science, Yokohama City University, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
Yuuki
Y
Asano
Department of Medical Life Science, Graduate School of Medical Life Science, Yokohama City University, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
Aritaka
A
Nagadoi
Department of Medical Life Science, Graduate School of Medical Life Science, Yokohama City University, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
Mamoru
M
Sato
Department of Electrical Engineering and Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo, 162-8480, Japan.
Hitoshi
H
Kurumizaka
Department of Medical Life Science, Graduate School of Medical Life Science, Yokohama City University, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
Yoshifumi
Y
Nishimura
Department of Medical Life Science, Graduate School of Medical Life Science, Yokohama City University, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
Satoko
S
Akashi
D000107:Acetylation; D000595:Amino Acid Sequence; D000818:Animals; D001120:Arginine / Q000737:chemistry; D006657:Histones / Q000737:chemistry*; D006801:Humans; D008239:Lysine / Q000737:chemistry; D008969:Molecular Sequence Data; D055503:Protein Multimerization; D055550:Protein Stability; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods
D006657:Histones; D001120:Arginine; D008239:Lysine
acetylation; deimination; electrospray ionization; histone H2A/H2B dimer; ion mobility-mass spectrometry