Molecular characterization and gene disruption of a novel zinc-finger protein, HIT-4, expressed in rodent brain.
To identify a novel regulatory factor involved in brain development or synaptic plasticity, we applied the differential display PCR method to mRNA samples from NMDA-stimulated and un-stimulated neocortical cultures. Among 64 cDNA clones isolated, eight clones were novel genes and one of them encodes a novel zinc-finger protein, HIT-4, which is 317 amino acid residues (36-38 kDa) in length and contains seven C2H2 zinc-finger motifs. Rat HIT-4 cDNA exhibits strong homology to human ZNF597 (57% amino acid identity and 72% homology) and identity to rat ZNF597 at the carboxyl region. Furthermore, genomic alignment of HIT-4 cDNA indicates that the alternative use of distinct promoters and exons produces HIT-4 and ZNF597 mRNAs. Northern blotting revealed that HIT-4 mRNA (approximately 6 kb) is expressed in various tissues such as the lung, heart, and liver, but enriched in the brain, while ZNF597 mRNA (approximately 1.5 kb) is found only in the testis. To evaluate biological roles of HIT-4/ZNF597, targeted mutagenesis of this gene was performed in mice. Homozygous (-/-) mutation was embryonic lethal, ceasing embryonic organization before cardiogenesis at embryonic day 7.5. Heterozygous (+/-) mice were able to survive but showing cell degeneration and vacuolization of the striatum, cingulate cortex, and their surrounding white matter. These results reveal novel biological and pathological roles of HIT-4 in brain development and/or maintenance.
Tanabe
Yasutaka
Y
Department of Molecular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan.
Hirano
Akiko
A
Iwasato
Takuji
T
Itohara
Shigeyoshi
S
Araki
Kazuaki
K
Yamaguchi
Tsuyoshi
T
Ichikawa
Tomio
T
Kumanishi
Toshiro
T
Aizawa
Yoshifusa
Y
Takahashi
Hitoshi
H
Kakita
Akiyoshi
A
Nawa
Hiroyuki
H
D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D018929:Cell Culture Techniques; D004622:Embryo, Mammalian; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D015723:Gene Library; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D016335:Zinc Fingers / Q000235:genetics*
D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; C547506:zinc finger protein 597, rat