Hairless is translocated to the nucleus via a novel bipartite nuclear localization signal and is associated with the nuclear matrix

Hair follicle cycling is an exquisitely regulated and dynamic process consisting of phases of growth, regression and quiescence. The transitions between the phases are governed by a growing number of regulatory proteins, including transcription factors. The hairless (hr) gene encodes a putative transcription factor that is highly expressed in the skin, where it appears to be an essential regulator during the regression of the catagen hair follicle. In hairless mice, as well as humans with congenital atrichia, the absence of hr gene function initiates a premature and abnormal catagen due to a dysregulation of apoptosis and cell adhesion, and defects in the signaling required for hair follicle remodeling. Here, we report structure-function studies of the hairless gene product, in which we identify a novel bipartite nuclear localization signal (NLS) of the form KRA(X13) PKR. Deletion analysis of the mouse hr gene mapped the NLS to amino acid residues 409–427. Indirect immunofluorescence microscopy of cells transiently transfected with hairless-green fluorescent fusion proteins demonstrated that these amino acid residues are necessary and sufficient for nuclear localization. Furthermore, nuclear fractionation analysis revealed that the hr protein is associated with components of the nuclear matrix.

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Characterization of the bipartite nuclear localization signal of protein LANA2 from Kaposi's sarcoma-associated herpesvirus

Biochemical Journal ◽

10.1042/bj20021890 ◽

2003 ◽

Vol 374 (2) ◽

pp. 545-550 ◽

Cited By ~ 7

Author(s):

Cesar MUÑOZ-FONTELA ◽

Estefanía RODRÍGUEZ ◽

Cesar NOMBELA ◽

Javier ARROYO ◽

Carmen RIVAS

Keyword(s):

Amino Acid ◽

Nuclear Localization ◽

Nuclear Localization Signal ◽

Kaposi's Sarcoma ◽

Molecular Mechanisms ◽

Kaposi’S Sarcoma ◽

Bipartite Nuclear Localization Signal ◽

Localization Signal ◽

Kaposi's Sarcoma Associated Herpesvirus ◽

Kaposi’S Sarcoma Associated Herpesvirus

LANA2 is a nuclear latent protein detected exclusively in Kaposi's sarcoma-associated herpesvirus-infected B cells. The protein inhibits p53-dependent transactivation and apoptosis, suggesting an important role in the transforming activity of the virus. To explore the molecular mechanisms of its nuclear localization, fusion proteins of green fluorescent protein (EGFP) and deletion constructs of LANA2 were expressed in HeLa cells. Only the fragment comprising amino acid residues 355–440 of LANA2 localized in the cell nucleus. This fragment contains two closely located basic domains and forms a putative bipartite nuclear localization signal (NLS). The putative LANA2 NLS was able to target EGFP to the nucleus consistently. Site-directed mutation analyses demonstrated that LANA2 contains a functional bipartite NLS between amino acid positions 367 and 384. In addition, analysis of cells transfected with a cytoplasmic LANA2 mutant revealed that an appropriate subcellular localization may be crucial to regulate p53 activity.

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Staufen1 is imported into the nucleolus via a bipartite nuclear localization signal and several modulatory determinants

Biochemical Journal ◽

10.1042/bj20050694 ◽

2005 ◽

Vol 393 (1) ◽

pp. 245-254 ◽

Cited By ~ 32

Author(s):

Catherine Martel ◽

Paolo Macchi ◽

Luc Furic ◽

Michael A. Kiebler ◽

Luc Desgroseillers

Keyword(s):

Nuclear Localization ◽

Nuclear Localization Signal ◽

Nuclear Export ◽

Mammalian Cells ◽

Rna Binding ◽

Binding Activity ◽

Nuclear Trafficking ◽

Binding Domains ◽

Bipartite Nuclear Localization Signal ◽

Localization Signal

Mammalian Stau1 (Staufen1), a modular protein composed of several dsRBDs (double-stranded RNA-binding domains), is probably involved in mRNA localization. Although Stau1 is mostly described in association with the rough endoplasmic reticulum and ribosomes in the cytoplasm, recent studies suggest that it may transit through the nucleus/nucleolus. Using a sensitive yeast import assay, we show that Stau1 is actively imported into the nucleus through a newly identified bipartite nuclear localization signal. As in yeast, the bipartite nuclear localization signal is necessary for Stau1 nuclear import in mammalian cells. It is also required for Stau1 nucleolar trafficking. However, Stau1 nuclear transit seems to be regulated by mechanisms that involve cytoplasmic retention and/or facilitated nuclear export. Cytoplasmic retention is mainly achieved through the action of dsRBD3, with dsRBD2 playing a supporting role in this function. Similarly, dsRBD3, but not its RNA-binding activity, is critical for Stau1 nucleolar trafficking. The function of dsRBD3 is strengthened or stabilized by the presence of dsRBD4 but prevented by the interdomain between dsRBD2 and dsRBD3. Altogether, these results suggest that Stau1 nuclear trafficking is a highly regulated process involving several determinants. The presence of Stau1 in the nucleus/nucleolus suggests that it may be involved in ribonucleoprotein formation in the nucleus and/or in other nuclear functions not necessarily related to mRNA transport.

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Identification of a novel bipartite nuclear localization signal in the DNA polymerase of the betabaculovirus Pieris rapae granulovirus

Archives of Virology ◽

10.1007/s00705-018-4115-0 ◽

2018 ◽

Vol 164 (3) ◽

pp. 839-845

Author(s):

Pei Li ◽

Lijuan Wu ◽

Guoqing Chen

Keyword(s):

Dna Polymerase ◽

Nuclear Localization ◽

Nuclear Localization Signal ◽

Pieris Rapae ◽

Bipartite Nuclear Localization Signal ◽

Localization Signal

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Use of a general purpose mammalian expression vector for studying intracellular protein targeting: identification of critical residues in the nuclear lamin A/C nuclear localization signal

Journal of Cell Science ◽

10.1242/jcs.105.2.481 ◽

1993 ◽

Vol 105 (2) ◽

pp. 481-488 ◽

Cited By ~ 3

Author(s):

J.V. Frangioni ◽

B.G. Neel

Keyword(s):

Amino Acid ◽

Nuclear Localization ◽

Nuclear Localization Signal ◽

Protein Targeting ◽

General Purpose ◽

Expression Vectors ◽

Intracellular Protein ◽

Mammalian Expression ◽

Nuclear Lamin ◽

Localization Signal

We have constructed a general purpose mammalian expression vector for the study of intracellular protein targeting. The vector, p3PK, facilitates construction of N- and/or C-terminal fusions of an amino acid sequence of interest to the normally cytosolic protein chicken muscle pyruvate kinase (CMPK). The vector has been engineered such that any fusion construct can be subcloned into the versatile pJx omega family of mammalian expression vectors and into pGEX bacterial expression vectors, for the generation of affinity reagents. In this paper, we demonstrate the general utility of p3PK by redirecting CMPK to mitochondria (using the twelve amino acid pre-sequence of yeast cytochrome c oxidase subunit IV) and to the nucleus (using a putative eight amino acid nuclear localization signal from human nuclear lamins A and C). We also report that, contrary to the predictions of previously published work, substitution of a critical residue in the nuclear lamin A/C nuclear localization signal (the equivalent of lysine 128 in the SV40 large T nuclear localization signal) retains nuclear localization, and discuss how amino acid context might affect targeting to the nucleus.

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The Sts1 nuclear import adapter uses a non-canonical bipartite nuclear localization signal and is directly degraded by the proteasome

Journal of Cell Science ◽

10.1242/jcs.236158 ◽

2020 ◽

Vol 133 (6) ◽

pp. jcs236158

Author(s):

Lauren Budenholzer ◽

Carolyn Breckel ◽

Christopher M. Hickey ◽

Mark Hochstrasser

Keyword(s):

Nuclear Localization ◽

Nuclear Import ◽

Nuclear Localization Signal ◽

Bipartite Nuclear Localization Signal ◽

Localization Signal

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Erratum: Identification of a functional bipartite nuclear localization signal in the tumor suppressor parafibromin

Oncogene ◽

10.1038/sj.onc.1210177 ◽

2007 ◽

Vol 26 (5) ◽

pp. 788-788

Author(s):

M A Hahn ◽

D J Marsh

Keyword(s):

Tumor Suppressor ◽

Nuclear Localization ◽

Nuclear Localization Signal ◽

Bipartite Nuclear Localization Signal ◽

Localization Signal

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Functional Identification of a Nuclear Localization Signal of MYB2 Protein in Giardia lamblia

The Korean Journal of Parasitology ◽

10.3347/kjp.2020.58.6.675 ◽

2020 ◽

Vol 58 (6) ◽

pp. 675-679

Author(s):

Juri Kim ◽

Mee Young Shin ◽

Soon-Jung Park

Keyword(s):

Transcription Factor ◽

Amino Acid ◽

Nuclear Localization ◽

Nuclear Import ◽

Nuclear Localization Signal ◽

Giardia Lamblia ◽

Nuclear Protein ◽

Functional Identification ◽

Localization Signal ◽

Nuclear Location

MYB2 protein was identified as a transcription factor that showed encystation-induced expression in Giardia lamblia. Although nuclear import is essential for the functioning of a transcription factor, an evident nuclear localization signal (NLS) of G. lamblia MYB2 (GlMYB2) has not been defined. Based on putative GlMYB2 NLSs predicted by 2 programs, a series of plasmids expressing hemagglutinin (HA)-tagged GlMYB2 from the promoter of G. lamblia glutamate dehydrogenase were constructed and transfected into Giardia trophozoites. Immunofluorescence assays using anti-HA antibodies indicated that GlMYB2 amino acid sequence #507–#530 was required for the nuclear localization of GlMYB2, and this sequence was named as NLSGlMYB2. We further verified this finding by demonstrating the nuclear location of a protein obtained by the fusion of NLSGlMYB2 and G. lamblia glyceraldehyde 3-phosphate dehydrogenase, a non-nuclear protein. Our data on GlMYB2 will expand our understanding on NLSs functioning in G. lamblia.

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