Person:
Nadarajan, Saravanapriah

Profile Picture

Email Address

AA Acceptance Date

Birth Date

Research Projects

Organizational Units

Job Title

Last Name

Nadarajan

First Name

Saravanapriah

Name

Nadarajan, Saravanapriah
Author's Publications: search.filters.isAuthorOfPublication.3ddbf5ee-d7d1-4dc6-bddb-918fe98c0964

Search Results

Now showing 1 - 4 of 4
  • Thumbnail Image
    Publication
    Investigating the Role of RIO Protein Kinases in Caenorhabditis elegans
    (Public Library of Science, 2015) Mendes, Tasha K.; Novakovic, Stevan; Raymant, Greta; Bertram, Sonja E.; Esmaillie, Reza; Nadarajan, Saravanapriah; Breugelmans, Bert; Hofmann, Andreas; Gasser, Robin B.; Colaiacovo, Monica; Boag, Peter R.
    RIO protein kinases (RIOKs) are a relatively conserved family of enzymes implicated in cell cycle control and ribosomal RNA processing. Despite their functional importance, they remain a poorly understood group of kinases in multicellular organisms. Here, we show that the C. elegans genome contains one member of each of the three RIOK sub-families and that each of the genes coding for them has a unique tissue expression pattern. Our analysis showed that the gene encoding RIOK-1 (riok-1) was broadly and strongly expressed. Interestingly, the intestinal expression of riok-1 was dependent upon two putative binding sites for the oxidative and xenobiotic stress response transcription factor SKN-1. RNA interference (RNAi)-mediated knock down of riok-1 resulted in germline defects, including defects in germ line stem cell proliferation, oocyte maturation and the production of endomitotic oocytes. Taken together, our findings indicate new functions for RIOK-1 in post mitotic tissues and in reproduction.
  • Thumbnail Image
    Publication
    The MAP kinase pathway coordinates crossover designation with disassembly of synaptonemal complex proteins during meiosis
    (eLife Sciences Publications, Ltd, 2016) Nadarajan, Saravanapriah; Mohideen, Firaz; Tzur, Yonatan B; Ferrandiz, Nuria; Crawley, Oliver; Montoya, Alex; Faull, Peter; Snijders, Ambrosius P; Cutillas, Pedro R; Jambhekar, Ashwini; Blower, Michael; Martinez-Perez, Enrique; Harper, J Wade; Colaiacovo, Monica
    Asymmetric disassembly of the synaptonemal complex (SC) is crucial for proper meiotic chromosome segregation. However, the signaling mechanisms that directly regulate this process are poorly understood. Here we show that the mammalian Rho GEF homolog, ECT-2, functions through the conserved RAS/ERK MAP kinase signaling pathway in the C. elegans germline to regulate the disassembly of SC proteins. We find that SYP-2, a SC central region component, is a potential target for MPK-1-mediated phosphorylation and that constitutively phosphorylated SYP-2 impairs the disassembly of SC proteins from chromosomal domains referred to as the long arms of the bivalents. Inactivation of MAP kinase at late pachytene is critical for timely disassembly of the SC proteins from the long arms, and is dependent on the crossover (CO) promoting factors ZHP-3/RNF212/Zip3 and COSA-1/CNTD1. We propose that the conserved MAP kinase pathway coordinates CO designation with the disassembly of SC proteins to ensure accurate chromosome segregation. DOI: http://dx.doi.org/10.7554/eLife.12039.001
  • Thumbnail Image
    Publication
    Polo-like kinase-dependent phosphorylation of the synaptonemal complex protein SYP-4 regulates double-strand break formation through a negative feedback loop.
    (eLife Sciences Publications, Ltd, 2017) Nadarajan, Saravanapriah; Lambert, Talley; Altendorfer, Elisabeth; Gao, Jinmin; Blower, Michael; Waters, Jennifer; Colaiacovo, Monica
    The synaptonemal complex (SC) is an ultrastructurally conserved proteinaceous structure that holds homologous chromosomes together and is required for the stabilization of pairing interactions and the completion of crossover (CO) formation between homologs during meiosis I. Here, we identify a novel role for a central region component of the SC, SYP-4, in negatively regulating formation of recombination-initiating double-strand breaks (DSBs) via a feedback loop triggered by crossover designation in C. elegans. We found that SYP-4 is phosphorylated dependent on Polo-like kinases PLK-1/2. SYP-4 phosphorylation depends on DSB formation and crossover designation, is required for stabilizing the SC in pachytene by switching the central region of the SC from a more dynamic to a less dynamic state, and negatively regulates DSB formation. We propose a model in which Polo-like kinases recognize crossover designation and phosphorylate SYP-4 thereby stabilizing the SC and making chromosomes less permissive for further DSB formation. DOI: http://dx.doi.org/10.7554/eLife.23437.001
  • Thumbnail Image
    Publication
    LAB-1 Targets PP1 and Restricts Aurora B Kinase upon Entrance into Meiosis to Promote Sister Chromatid Cohesion
    (Public Library of Science, 2012) Egydio de Carvalho, Carlos; Van Bostelen, Ivo; Gu, Yanjie; Chu, Diana S.; Cheeseman, Iain M.; Tzur, Yonatan B; Nadarajan, Saravanapriah; Colaiacovo, Monica
    Successful execution of the meiotic program depends on the timely establishment and removal of sister chromatid cohesion. LAB-1 has been proposed to act in the latter by preventing the premature removal of the meiosis-specific cohesin REC-8 at metaphase I in C. elegans, yet the mechanism and scope of LAB-1 function remained unknown. Here we identify an unexpected earlier role for LAB-1 in promoting the establishment of sister chromatid cohesion in prophase I. LAB-1 and REC-8 are both required for the chromosomal association of the cohesin complex subunit SMC-3. Depletion of lab-1 results in partial loss of sister chromatid cohesion in rec-8 and coh-4 coh-3 mutants and further enhanced chromatid dissociation in worms where all three kleisins are mutated. Moreover, lab-1 depletion results in increased Aurora B kinase (AIR-2) signals in early prophase I nuclei, coupled with a parallel decrease in signals for the PP1 homolog, GSP-2. Finally, LAB-1 directly interacts with GSP-1 and GSP-2. We propose that LAB-1 targets the PP1 homologs to the chromatin at the onset of meiosis I, thereby antagonizing AIR-2 and cooperating with the cohesin complex to promote sister chromatid association and normal progression of the meiotic program.