Characterization of the PR domain of RIZ1 histone methyltransferase.
RIZ1 (PRDM2) and PRDI-BF1 (PRDM1) are involved in B cell differentiation and the development of B cell lymphomas. These proteins are expressed in two forms that differ by the presence or absence of a PR domain. The protein product that retains the PR domain is anti-tumorigenic while the product that lacks the PR domain is oncogenic and over-expressed in tumor cells. The conserved PR domain is homologous to the SET domain from a family of histone methyltransferases. RIZ1 is also a histone methyltransferase and methylates lysine 9 in histone H3. This activity has been mapped to the PR domain. In the present study, deuterium exchange mass spectrometry was used to define the structural boundaries of the RIZ1 PR domain and to map sites of missense mutations that occur in human cancers and reduce methyltransferase activity. Flexible segments were selectively deleted to produce protein products that crystallize for structural studies. Segments at the carboxyl terminus of the PR domain that are involved in methylation of H3 were shown to be flexible, similar to SET domains, suggesting that the PR and SET methyltransferases may belong to an emerging class of proteins that contain mobile functional regions.
Derunes
Céline
C
Cancer Center, The Burnham Institute, La Jolla, CA 92037, USA.
Briknarová
Klára
K
Geng
Liqing
L
Li
Sheng
S
Gessner
Chris R
CR
Hewitt
Krissi
K
Wu
ShuangDing
S
Huang
Shi
S
Woods
Virgil I
VI
Ely
Kathryn R
KR
D000595:Amino Acid Sequence; D001483:Base Sequence; D003460:Crystallization; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D004591:Electrophoresis, Polyacrylamide Gel; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D013058:Mass Spectrometry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D009687:Nuclear Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology
D017931:DNA Primers; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors; D011495:Histone-Lysine N-Methyltransferase; C093563:PRDM2 protein, human