Differential expression and cellular localization of ZNF224 and ZNF255, two isoforms of the Krüppel-like zinc-finger protein family.
We previously reported that ZNF224, a novel Krüppel-associated box-containing zinc-finger protein, represses aldolase A gene transcription by interacting with the KAP-1 co-repressor. Using northern blot and PCR procedures, we now demonstrate that the transcript encoding ZNF255 is a ZNF224 isoform and that the corresponding mRNAs are differentially expressed in human adult and foetal tissues. Moreover, transient transfection of recombinant ZNF224 and ZNF255 proteins and chromatin-immunoprecipitation assays indicate that ZNF224 binds the negative regulatory element of the aldolase A gene (AldA-NRE) and inhibits transcription more efficiently than ZNF255. Finally, ZNF224 was homogeneously distributed in the nucleus, whereas its isoform ZNF255 was identified in subnuclear structures in association with nucleoli, and also in the cytoplasm. The different repression of transcription and the different cellular localization of ZNF224 and ZNF255 suggest these proteins exert different biological role.
Medugno
Lina
L
Dipartimento di Biochimica e Biotecnologie Mediche, Università di Napoli "Federico II", Via S. Pansini 5, 80131 Napoli, Italy.
Florio
Francesca
F
Cesaro
Elena
E
Grosso
Michela
M
Lupo
Angelo
A
Izzo
Paola
P
Costanzo
Paola
P
D000328:Adult; D015152:Blotting, Northern; D002460:Cell Line; D002466:Cell Nucleolus / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism*; D047369:Chromatin Immunoprecipitation; D003593:Cytoplasm / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004622:Embryo, Mammalian; D005456:Fluorescent Dyes; D005634:Fructose-Bisphosphate Aldolase / Q000235:genetics; D005786:Gene Expression Regulation; D006367:HeLa Cells; D006801:Humans; D007211:Indoles; D007668:Kidney / Q000166:cytology; D008957:Models, Genetic; D010957:Plasmids; D016133:Polymerase Chain Reaction; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D012045:Regulatory Sequences, Nucleic Acid; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D016335:Zinc Fingers / Q000235:genetics*
D004268:DNA-Binding Proteins; D005456:Fluorescent Dyes; D007211:Indoles; D020033:Protein Isoforms; D012333:RNA, Messenger; D011994:Recombinant Proteins; D012097:Repressor Proteins; C470003:ZNF224 protein, human; C007293:DAPI; D005634:Fructose-Bisphosphate Aldolase