Identification and characterization of JunD missense mutants that lack menin binding

Knapp, Jon-Michael; Heppner, Christina; Hickman, A.B.; Burns, A. Lee; Chandrasekharappa, Settara C.; Collins, Francis S.; Marx, Stephen J.; Spiegel, Allen M.; Agarwal, Sunita K.

doi:10.1038/sj.onc.1203832

Cited by 30 publications

(20 citation statements)

References 35 publications

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“…This differential interaction of Menin is the most significant functional difference identified between JunD-FL and ⌬JunD to date and suggests that a balance of activity between the two JunD isoforms may be important in regulating cell proliferation. Residues in JunD-FL have been identified that are important for Menin-JunD-FL binding (50). These residues (Pro 41 , Gly 42 , and Pro 44 ) are close to the JNK docking domain that we have identified in this study.…”

Section: Discussionmentioning

confidence: 78%

Regulation of Two JunD Isoforms by Jun N-terminal Kinases

Yazgan

Pfarr

2002

Journal of Biological Chemistry

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The JunD transcription factor is one member of the Jun family of proteins that also includes c-Jun and JunB. Although c-Jun can function to promote cell proliferation and can cooperate with other oncogenes to transform cells, JunD slows proliferation of fibroblasts and antagonizes transformation by activated ras. Two isoforms of JunD, a full-length isoform containing 341 amino acids (JunD-FL) and a truncated isoform lacking 48 amino acids at the N terminus (⌬JunD), are generated through utilization of two translation start sites within a single mRNA. Here we show that both isoforms of JunD are phosphorylated by Jun N-terminal kinases (JNKs) at three identical residues and that both contain a docking domain that specifically binds JNKs. The JunD-FL isoform binds to and is phosphorylated by JNK more efficiently than ⌬JunD in vitro; correspondingly, JunD-FL is a more potent transcriptional activator than ⌬JunD. Although increased JNK signaling can activate both JunD isoforms, mutating either the JNK docking domain or the target JNK phosphorylation sites blocks this activation. These results identify two distinct isoforms of JunD with differential responses to JNK signaling pathways.

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Section: Discussionmentioning

confidence: 78%

Regulation of Two JunD Isoforms by Jun N-terminal Kinases

Yazgan

Pfarr

2002

Journal of Biological Chemistry

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“…This region has been speculated to account for striking functional differences between JunD and other Jun proteins (25)(26)(27). This region, and specifically amino acids 41-44 (in mJunD), is essential for JunD binding to menin (11,28). The current findings indicate that the contrasting effects of JunD and cJun on growth indices (cell proliferation, cell morphology, and cyclin D1 levels) likely result from their contrasting interactions with menin at or near to these N-terminal sequences.…”

Section: Discussionmentioning

confidence: 99%

“…Plasmid constructs for stable transfections were made in the pcDNA3.1-hygro vector (Invitrogen). The inserts from pcDNA3.1-mouse-JunD, pcDNA3.1-mouse-JunD G42E , or pcDNA3.1-cJun (4,11) were excised with HindIII/NotI and ligated into the corresponding sites of the pcDNA3.1-hygro vector (named pcDNA3.1-hygro-mJunD, pcDNA3.1-hygromJunD G42E , and pcDNA3.1-hygro-cJun). Immortalized fibroblasts were transfected and selected in medium containing hygromycin-B, 300 g/ml for Men1-WT-10 and Men1-NULL-17; 500 g/ml for JunD-NULL-2; and 600 g/ml for Men1-NULL-41.…”

Section: Methodsmentioning

confidence: 99%

Transcription factor JunD, deprived of menin, switches from growth suppressor to growth promoter

Agarwal

Novotny

Crabtree

et al. 2003

Proc. Natl. Acad. Sci. U.S.A.

112

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“…Recombinant human menin was purified as previously described (37). For purification of the RPA heterotrimer, E. coli BL21(DE3) transformed with pET11a rpa1 ⅐ 3 ⅐ 2 was induced with 0.5 mM isopropyl ␤-D-thiogalactopyranoside and grown at room temperature with shaking for 7 h. Cells were pelleted by centrifugation, frozen in a dry ice-methanol bath, and stored at Ϫ80°C until needed.…”

Section: Methodsmentioning

confidence: 99%

“…Glutathione-Sepharose-bound proteins were prepared as described for free GST and GST-RPA2 except that purification was halted prior to the elution step. FLAG-BAP and FLAG-menin proteins bound to anti-Flag-agarose were prepared as described by Knapp et al (37).…”

Section: Methodsmentioning

confidence: 99%

The 32-Kilodalton Subunit of Replication Protein A Interacts with Menin, the Product of the MEN1 Tumor Suppressor Gene

Sukhodolets

Hickman

Agarwal

et al. 2003

Molecular and Cellular Biology

111

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Menin is a 70-kDa protein encoded by MEN1, the tumor suppressor gene disrupted in multiple endocrine neoplasia type 1. In a yeast two-hybrid system based on reconstitution of Ras signaling, menin was found to interact with the 32-kDa subunit (RPA2) of replication protein A (RPA), a heterotrimeric protein required for DNA replication, recombination, and repair. The menin-RPA2 interaction was confirmed in a conventional yeast two-hybrid system and by direct interaction between purified proteins. Menin-RPA2 binding was inhibited by a number of menin missense mutations found in individuals with multiple endocrine neoplasia type 1, and the interacting regions were mapped to the N-terminal portion of menin and amino acids 43 to 171 of RPA2. This region of RPA2 contains a weak single-stranded DNA-binding domain, but menin had no detectable effect on RPA-DNA binding in vitro. Menin bound preferentially in vitro to free RPA2 rather than the RPA heterotrimer or a subcomplex consisting of RPA2 bound to the 14-kDa subunit (RPA3). However, the 70-kDa subunit (RPA1) was coprecipitated from HeLa cell extracts along with RPA2 by menin-specific antibodies, suggesting that menin binds to the RPA heterotrimer or a novel RPA1-RPA2-containing complex in vivo. This finding was consistent with the extensive overlap in the nuclear localization patterns of endogenous menin, RPA2, and RPA1 observed by immunofluorescence.Multiple endocrine neoplasia type 1 is a rare, autosomal dominant tumor syndrome, typically defined by the presence of tumors in at least two of the following three tissues: the parathyroid, enteropancreatic endocrine tissue, and the anterior pituitary (reviewed in reference 46). The human MEN1 gene was identified by positional cloning in 1997 (13) and shown to encode a 610-amino-acid product (menin) with predominantly nuclear localization (24). Loss of heterozygosity in the region containing the MEN1 locus has been observed in tumor tissue obtained from individuals with multiple endocrine neoplasia type 1 (39) and from mice with an engineered deletion in one of their Men1 alleles (16), predictive of a tumor suppressor function. This is supported by the detection of MEN1 frameshift or nonsense mutations in approximately 70% of human multiple endocrine neoplasia type 1 tumors (46). Menin overexpression has also been shown to diminish the tumorigenic phenotype of Ras-transformed NIH 3T3 cells (36), consistent with its putative tumor suppressor function. Knockout of both Men1 alleles in mice has been shown to result in embryonic lethality (16), suggesting that menin is also important for early development. However, the absence of significant homology to other proteins has complicated efforts to elucidate the function(s) of menin and/or the mechanisms of its tumor suppressor activity.A number of menin-interacting proteins have been identified in an effort to obtain clues about menin function, including the AP-1 transcription factor JunD (2), the putative tumor metastasis suppressor/nucleoside diphosphate kinase nm23 (54), the...

show abstract

Identification and characterization of JunD missense mutants that lack menin binding

Cited by 30 publications

References 35 publications

Regulation of Two JunD Isoforms by Jun N-terminal Kinases

Regulation of Two JunD Isoforms by Jun N-terminal Kinases

Transcription factor JunD, deprived of menin, switches from growth suppressor to growth promoter

The 32-Kilodalton Subunit of Replication Protein A Interacts with Menin, the Product of the MEN1 Tumor Suppressor Gene

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