Splice variants of the dual specificity tyrosine phosphorylation-regulated kinase 4 (DYRK4) differ in their subcellular localization and catalytic activity.
Dual specificity tyrosine phosphorylation-regulated kinases, DYRKs, are a family of conserved protein kinases that play key roles in the regulation of cell differentiation, proliferation, and survival. Of the five mammalian DYRKs, DYRK4 is the least studied family member. Here, we show that several splice variants of DYRK4 are expressed in tissue-specific patterns and that these variants have distinct functional capacities. One of these variants contains a nuclear localization signal in its extended N terminus that mediates its interaction with importin α3 and α5 and that is capable of targeting a heterologous protein to the nucleus. Consequently, the nucleocytoplasmic mobility of this variant differs from that of a shorter isoform in live cell imaging experiments. Other splicing events affect the catalytic domain, including a three-amino acid deletion within subdomain XI that markedly reduces the enzymatic activity of DYRK4. We also show that autophosphorylation of a tyrosine residue within the activation loop is necessary for full DYRK4 kinase activity, a defining feature of the DYRK family. Finally, by comparing the phosphorylation of an array of 720 peptides, we show that DYRK1A, DYRK2, and DYRK4 differ in their target recognition sequence and that preference for an arginine residue at position P -3 is a feature of DYRK1A but not of DYRK2 and DYRK4. Therefore, we highlight the use of subcellular localization as an important regulatory mechanism for DYRK proteins, and we propose that substrate specificity could be a source of functional diversity among DYRKs.
Genes and Disease Program, Centre for Genomic Regulation, University Pompeu Fabra, Dr Aiguader 88, 08003 Barcelona, Spain.
Chrisovalantis
C
Papadopoulos
Krisztina
K
Arato
Eva
E
Lilienthal
Johannes
J
Zerweck
Mike
M
Schutkowski
Nicolas
N
Chatain
Gerhard
G
Müller-Newen
Walter
W
Becker
Susana
S
de la Luna
D017398:Alternative Splicing / Q000502:physiology*; D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D057809:HEK293 Cells; D006801:Humans; D051379:Mice; D009928:Organ Specificity / Q000502:physiology; D010766:Phosphorylation / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary / Q000502:physiology; D021381:Protein Transport / Q000502:physiology; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity / Q000502:physiology; D000097603:Dyrk Kinases
D017346:Protein Serine-Threonine Kinases; D011505:Protein-Tyrosine Kinases; D000097603:Dyrk Kinases