Identification and characterization of two forms of mouse MUTYH proteins encoded by alternatively spliced transcripts.
There are three types of mouse Mutyh mRNAs (type a, b and c) generated by alternative splicing, and type b mRNA is a major form among the three in most of the tissues examined. The level of type c mRNA is relatively high in brain. Type a and b mRNAs were expected to encode 57.7 kDa protein (MUTYHalpha), while type c mRNA had a partly different open reading frame encoding a 50.2 kDa protein (MUTYHbeta). An in vitro translation of type b and c mRNAs produced a 50 kDa MUTYHalpha and 47 kDa MUTYHbeta, respectively. MUTYHalpha and MUTYHbeta were detected in wild-type embryonic stem (ES) cells or thymocytes prepared from wild-type mice, but neither MUTYH-null ES cells nor thymocytes prepared from MUTYH-null mice. Both MUTYHalpha and MUTYHbeta were mainly localized in the nuclei and some in mitochondria in wild-type ES cells. Recombinant MUTYHalpha and beta were expressed as fusion proteins with thioredoxin in Escherichia coli, but only MUTYHalpha was partly soluble and thus could be purified. Recombinant MUTYHalpha possessed DNA glycosylase activities to excise adenine opposite 8-oxoguanine and guanine but not AP lyase activity.
Ichinoe
Akimasa
A
Division of Neurofunctional Genomics, Department of Immunobiology and Neuroscience, Medical Institute of Bioregulation, Kyushu University, Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Fukuoka.
Behmanesh
Mehrdad
M
Tominaga
Yohei
Y
Ushijima
Yasuhiro
Y
Hirano
Seiki
S
Sakai
Yasunari
Y
Tsuchimoto
Daisuke
D
Sakumi
Kunihiko
K
Wake
Norio
N
Nakabeppu
Yusaku
Y
D000225:Adenine / Q000378:metabolism; D017398:Alternative Splicing / Q000235:genetics*; D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000201:enzymology; D045647:DNA Glycosylases / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000378:metabolism; D017353:Gene Deletion; D006147:Guanine / Q000031:analogs & derivatives* / Q000378:metabolism; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008928:Mitochondria / Q000201:enzymology; D008969:Molecular Sequence Data; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins; D012995:Solubility; D013234:Stem Cells / Q000201:enzymology; D013950:Thymus Gland / Q000166:cytology / Q000201:enzymology
D007527:Isoenzymes; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; C024829:8-hydroxyguanine; D006147:Guanine; D045647:DNA Glycosylases; C061738:mutY adenine glycosylase; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase; D000225:Adenine