Phosphatidylinositol-4-phosphate 5-Kinase 1α Modulates Ribosomal RNA Gene Silencing through Its Interaction with Histone H3 Lysine 9 Trimethylation and Heterochromatin Protein HP1-α

Chakrabarti, Rajarshi; Sanyal, Sulagna; Ghosh, Amit; Bhar, Kaushik; Das, Chandrima; Siddhanta, Anirban

doi:10.1074/jbc.m114.633727

Cited by 24 publications

(13 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Star-PAP interacts with and localises PIP5K1A to the nucleus in order to increase the local production of PtdIns(4,5) P 2 . Thirdly, PIP5K1A is post-translationally modified by sumoylation [50,51] which controls its nuclear localisation and interaction with chromatin silencing complexes (Figure 4).…”

Section: Changes In the Localisation Or Activity Of Ppins Modulatimentioning

confidence: 99%

Nuclear Phosphoinositides: Their Regulation and Roles in Nuclear Functions

Fiume

Faenza

Sheth

et al. 2019

IJMS

View full text Add to dashboard Cite

Polyphosphoinositides (PPIns) are a family of seven lipid messengers that regulate a vast array of signalling pathways to control cell proliferation, migration, survival and differentiation. PPIns are differentially present in various sub-cellular compartments and, through the recruitment and regulation of specific proteins, are key regulators of compartment identity and function. Phosphoinositides and the enzymes that synthesise and degrade them are also present in the nuclear membrane and in nuclear membraneless compartments such as nuclear speckles. Here we discuss how PPIns in the nucleus are modulated in response to external cues and how they function to control downstream signalling. Finally we suggest a role for nuclear PPIns in liquid phase separations that are involved in the formation of membraneless compartments within the nucleus.

show abstract

Section: Changes In the Localisation Or Activity Of Ppins Modulatimentioning

confidence: 99%

Nuclear Phosphoinositides: Their Regulation and Roles in Nuclear Functions

Fiume

Faenza

Sheth

et al. 2019

IJMS

View full text Add to dashboard Cite

show abstract

“…The hallmarks of constitutive heterochromatin, HP1 and H3K9me3, were present in the common ancestor of fission yeast and human around one billion years ago [ 16 , 17 ]. Both are enriched at canonical sites of constitutive heterochromatin, the peri-centric regions, (sub-)telomeres and (peri-)nucleolar organisers [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ] and their function at these sites has been the subject of numerous studies in different organisms [ 213 , 227 ]. Less well studied are heterochromatin- like domains/complexes that share the hallmarks, HP1 and H3K9me3, with constitutive heterochromatin but lie outside the canonical constitutively heterochromatic territories [ 30 , 65 ].…”

Section: Discussionmentioning

confidence: 99%

“…HP1 and the H3K9me3 modification are highly conserved across eukaryotes and represent hallmarks of constitutive heterochromatin [ 16 , 17 ] that are enriched at constitutively heterochromatic chromosomal territories of nearly all eukaryotic chromosomes. These territories include peri-centric heterochromatin surrounding the centromeres, (sub-)telomeric and (peri-)nucleolar organiser regions (NORs), with both hallmarks being found at these sites in organisms as distantly related as fission yeast through Drosophila to human [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. Notable exceptions are the chromosomes of budding yeast where the silent information regulator (Sir) complex is assembled at heterochromatic territories (telomeres and NORs) by establishing and recognising a pattern of de-acetylated histones, especially hypo-acetylated H4K16 [ 26 ].…”

Section: Introductionmentioning

confidence: 99%

Biology and Physics of Heterochromatin-Like Domains/Complexes

Singh

Belyakin

Laktionov

2020

Cells

View full text Add to dashboard Cite

The hallmarks of constitutive heterochromatin, HP1 and H3K9me2/3, assemble heterochromatin-like domains/complexes outside canonical constitutively heterochromatic territories where they regulate chromatin template-dependent processes. Domains are more than 100 kb in size; complexes less than 100 kb. They are present in the genomes of organisms ranging from fission yeast to human, with an expansion in size and number in mammals. Some of the likely functions of domains/complexes include silencing of the donor mating type region in fission yeast, preservation of DNA methylation at imprinted germline differentially methylated regions (gDMRs) and regulation of the phylotypic progression during vertebrate development. Far cis- and trans-contacts between micro-phase separated domains/complexes in mammalian nuclei contribute to the emergence of epigenetic compartmental domains (ECDs) detected in Hi-C maps. A thermodynamic description of micro-phase separation of heterochromatin-like domains/complexes may require a gestalt shift away from the monomer as the “unit of incompatibility” that determines the sign and magnitude of the Flory–Huggins parameter, χ. Instead, a more dynamic structure, the oligo-nucleosomal “clutch”, consisting of between 2 and 10 nucleosomes is both the long sought-after secondary structure of chromatin and its unit of incompatibility. Based on this assumption we present a simple theoretical framework that enables an estimation of χ for domains/complexes flanked by euchromatin and thereby an indication of their tendency to phase separate. The degree of phase separation is specified by χN, where N is the number of “clutches” in a domain/complex. Our approach could provide an additional tool for understanding the biophysics of the 3D genome.

show abstract

“…However, we did not observe any obvious asymmetrical localization of PIP2 in the embryos, and thus provide more support for another proposal, that PPK-1 might influence the spindle positioning independently of its function as a PIP2 producer. Suggestions about the independent role of PI5PK and PIP2 were previously published by us [ 18 ] and Chakrabarti et al for the regulation of the RNA polymerase I transcription in mammalian cells [ 46 ].…”

Section: Discussionmentioning

confidence: 99%

“…On the other hand, PPK-1 per se may contribute to the regulation of these processes independently of its function as a PIP2 producer, and possibly by the interaction with different protein binding partners, too. Previously, a distinct role of PIP2 and its kinase has been described, based on the binding partners for mammalian cell lines [ 18 , 46 ]. Partially, some of the observed phenotypes might be indirect, caused by the decrease of the second messengers produced by the PIP2 cleavage.…”

Section: Discussionmentioning

confidence: 99%

Multiple Aspects of PIP2 Involvement in C. elegans Gametogenesis

Ulicna

Rohožková

Hozák

2018

IJMS

View full text Add to dashboard Cite

One of the most studied phosphoinositides is phosphatidylinositol 4,5-bisphosphate (PIP2), which localizes to the plasma membrane, nuclear speckles, small foci in the nucleoplasm, and to the nucleolus in mammalian cells. Here, we show that PIP2 also localizes to the nucleus in prophase I, during the gametogenesis of C. elegans hermaphrodite. The depletion of PIP2 by type I PIP kinase (PPK-1) kinase RNA interference results in an altered chromosome structure and leads to various defects during meiotic progression. We observed a decreased brood size and aneuploidy in progeny, defects in synapsis, and crossover formation. The altered chromosome structure is reflected in the increased transcription activity of a tightly regulated process in prophase I. To elucidate the involvement of PIP2 in the processes during the C. elegans development, we identified the PIP2-binding partners, leucine-rich repeat (LRR-1) protein and proteasome subunit beta 4 (PBS-4), pointing to its involvement in the ubiquitin–proteasome pathway.

show abstract

Phosphatidylinositol-4-phosphate 5-Kinase 1α Modulates Ribosomal RNA Gene Silencing through Its Interaction with Histone H3 Lysine 9 Trimethylation and Heterochromatin Protein HP1-α

Cited by 24 publications

References 37 publications

Nuclear Phosphoinositides: Their Regulation and Roles in Nuclear Functions

Nuclear Phosphoinositides: Their Regulation and Roles in Nuclear Functions

Biology and Physics of Heterochromatin-Like Domains/Complexes

Multiple Aspects of PIP2 Involvement in C. elegans Gametogenesis

Contact Info

Product

Resources

About