The MYO1F, unconventional myosin type 1F, gene is fused to MLL in infant acute monocytic leukemia with a complex translocation involving chromosomes 7, 11, 19 and 22.
We analysed a complex translocation involving chromosomes 7, 11, 19 and 22 in infant acute monocytic leukemia, and identified that the MLL gene on 11q23 was fused to the unconventional myosin type 1F, MYO1F, gene on 19p13.2-13.3. MYO1F consists of at least 28 exons and was predicted to encode a 1098-amino-acid with an N-terminal head domain containing both ATP-binding and actin-binding sequences, a neck domain with a single IQ motif, and a tail with TH1, TH2 and SH3 domains. Northern blot analysis of RNAs prepared from multiple tissues showed that the expression of approximately 4-kb transcripts appeared constant in most tissues examined. However, MYO1F was expressed in only three of 22 leukemic cell lines. The MLL-MYO1F fusion protein contains almost the entire MYO1F, however, C-terminal MYO1F has neither the transactivation domain nor the dimerization domain found in various MLL fusion partners. Further analysis of this novel type of MLL fusion protein would provide new insights into leukemogenesis. MYO1F is the fourth partner gene of MLL on 19p13. At the cytogenetic level, it may be difficult to distinguish MLL-ENL, MLL-ELL, MLL-EEN and MLL-MYO1F fusions created by t(11;19)(q23;p13), and it is likely that cases of t(11;19) lacking a known fusion gene may result in this gene fusion.
Taki
Tomohiko
T
Department of Molecular Laboratory Medicine, Kyoto Prefectural University of Medicine Graduate School of Medical Science, 465 Kajii-cho Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
Akiyama
Masaharu
M
Saito
Shinobu
S
Ono
Ryoichi
R
Taniwaki
Masafumi
M
Kato
Yoko
Y
Yuza
Yuki
Y
Eto
Yoshikatsu
Y
Hayashi
Yasuhide
Y
D000595:Amino Acid Sequence; D001483:Base Sequence; D045744:Cell Line, Tumor; D002880:Chromosomes, Human, Pair 11; D002888:Chromosomes, Human, Pair 19; D002892:Chromosomes, Human, Pair 22; D002897:Chromosomes, Human, Pair 7; D004268:DNA-Binding Proteins / Q000235:genetics*; D005260:Female; D015321:Gene Rearrangement; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D007223:Infant; D007948:Leukemia, Monocytic, Acute / Q000235:genetics*; D008969:Molecular Sequence Data; D051788:Myeloid-Lymphoid Leukemia Protein; D024461:Myosin Type I / Q000235:genetics*; D011519:Proto-Oncogenes / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D014178:Translocation, Genetic
D004268:DNA-Binding Proteins; C497422:KMT2A protein, human; D014157:Transcription Factors; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase; D024461:Myosin Type I