Kajava AV, Terskikh A, Tan PBO, Weissman I, Fradkov A, Ermakova G, Zhao X, Zaraisky A, Matz M, Siebert P, Lukyanov S, Kim SK
[
Science,
2000]
We generated a mutant of the red fluorescent protein drFP583. The mutant (E5) changes its fluorescence from green to red over time. The rate of color conversion is independent of protein concentration and therefore can be used to trace time-dependent expression. We used in vivo labeling with E5 to measure expression from the heat shock-dependent promoter in Caenorhabditis elegans and from the Otx-2 promoter in developing Xenopus embryos. Thus, E5 is a "fluorescent timer" that can be used to monitor both activation and down-regulation of target promoters on the whole-organism scale.AD - School of Medicine, Stanford University, Stanford, CA 94305, USA. Alexey.Terskikh@Stanford.eduFAU - Terskikh, AAU - Terskikh AFAU - Fradkov, AAU - Fradkov AFAU - Ermakova, GAU - Ermakova GFAU - Zaraisky, AAU - Zaraisky AFAU - Tan, PAU - Tan PFAU - Kajava, A VAU - Kajava AVFAU - Zhao, XAU - Zhao XFAU - Lukyanov, SAU - Lukyanov SFAU - Matz, MAU - Matz MFAU - Kim, SAU - Kim SFAU - Weissman, IAU - Weissman IFAU - Siebert, PAU - Siebert PLA - engID - 1 RO3 TW01362-01/TW/FICPT - Journal ArticleCY - UNITED STATESTA - ScienceJID - 0404511RN - 0 (Heat-Shock Proteins)RN - 0 (Luminescent Proteins)RN - 0 (Nerve Tissue Proteins)RN - 0 (Otx2 protein)RN - 0 (Trans-Activators)RN - 0 (red fluorescent protein)SB - IM
[
PLoS Biol,
2018]
Zinc is an essential mineral, but our understanding of its uses in the body is limited. Capitalizing on approaches available in the model system Caenorhabditis elegans, Zhao and colleagues show that zinc transduces a signal that induces sperm to become motile. This is an enigmatic process because sperm in all sexually-reproducing animals are transcriptionally inactive. Zinc levels inside sperm are regulated by an evolutionarily conserved zinc transporter called Zrt- and Irt-like Protein Transporter 7.1 (ZIPT-7.1). This zinc transporter localizes to intracellular organelles, suggesting that it primarily controls zinc levels by releasing zinc into the cytoplasm from internal stores rather than importing it from the external environment. The zinc released within cells acts as a messenger in a signaling pathway to promote mobility acquisition. These studies reveal an important role for zinc as an intracellular second messenger that generates physiological changes vital for sperm motility and fertility.
[
MicroPubl Biol,
2020]
RNA-seq is widely used for the quantitative analysis of transcriptomes in the context of studies of gene expression and regulation (Mortazavi et al., 2008; Ozsolak and Milos, 2011; Wang et al., 2009). Generally, RNA-seq protocols employ poly(A) selection for mRNA enrichment. However, poly(A) based enrichment is subject to potential bias depending on the poly(A) status of various mRNAs, which could be particularly undesirable in the context of studying post-transcriptional gene regulatory mechanisms, such miRNA repression (Wu et al., 2006). Therefore, ribosomal RNA (rRNA) depletion is a desirable alternative strategy to enrich for mRNA sequences in RNA-seq sample preparation (Zhao et al., 2014). However, currently available rRNA depletion toolkits were designed for either mammals or bacteria, and hence do not offer an efficient option for rRNA depletion of RNA samples from certain experimental organisms, such as C. elegans.
[
MicroPubl Biol,
2021]
The mitochondrial unfolded protein response (mitoUPR) is a stress response pathway that promotes cell survival and restores mitochondrial function when mitochondrial health is compromised (Haynes et al. 2013; Jovaisaite et al. 2014; Shpilka and Haynes 2018). While a mitoUPR was first reported in mammalian cells (Zhao et al. 2002), the initial work on the mitoUPR in C. elegans was performed by Yoneda et al. who found that treatment with ethidium bromide, which affects the replication and expression of mitochondrial DNA, increased the expression of the mitochondrial chaperone gene
hsp-6 (Yoneda et al. 2004). Based on this observation, they generated
hsp-6p::gfp and
hsp-60p::gfp reporter strains to further study the mitoUPR. They found that either RNA interference (RNAi) targeting
spg-7, the worm homolog of paraplegin, or RNAi targeting other genes encoding mitochondrial proteins resulted in activation of the
hsp-6p::gfp and
hsp-60p::gfp reporter strains (Yoneda et al. 2004).
Takacs-Vellai K, Qin J, Farkas Z, Jung SY, Kovacs T, Szondy Z, Sandor S, Shakir MA, Zhou Z, Boissan M, Liu X, Mehta A, Budai Z, Rajnavolgyi E, Bajtay Z, Petric M, Niedergang F, Orban TI, Herit F
[
FASEB J,
2019]
Phagocytosis of various targets, such as apoptotic cells or opsonized pathogens, by macrophages is coordinated by a complex signaling network initiated by distinct phagocytic receptors. Despite the different initial signaling pathways, each pathway ends up regulating the actin cytoskeletal network, phagosome formation and closure, and phagosome maturation leading to degradation of the engulfed particle. Herein, we describe a new phagocytic function for the nucleoside diphosphate kinase 1 (NDK-1), the nematode counterpart of the first identified metastasis inhibitor NM23-H1 (nonmetastatic clone number 23) nonmetastatic clone number 23 or nonmetastatic isoform 1 (NME1). We reveal by coimmunoprecipitation, Duolink proximity ligation assay, and mass spectrometry that NDK-1/NME1 works in a complex with DYN-1/Dynamin (<i>Caenorhabditis elegans</i>/human homolog proteins), which is essential for engulfment and phagosome maturation. Time-lapse microscopy shows that NDK-1 is expressed on phagosomal surfaces during cell corpse clearance in the same time window as DYN-1. Silencing of NM23-M1 in mouse bone marrow-derived macrophages resulted in decreased phagocytosis of apoptotic thymocytes. In human macrophages, NM23-H1 and Dynamin are corecruited at sites of phagosome formation in F-actin-rich cups. In addition, NM23-H1 was required for efficient phagocytosis. Together, our data demonstrate that NDK-1/NME1 is an evolutionarily conserved element of successful phagocytosis.-Farkas, Z., Petric, M., Liu, X., Herit, F., Rajnavolgyi, E., Szondy, Z., Budai, Z., Orban, T. I., Sandor, S., Mehta, A., Bajtay, Z., Kovacs, T., Jung, S. Y., Shakir, M. A., Qin, J., Zhou, Z., Niedergang, F., Boissan, M., Takacs-Vellai, K. The nucleoside diphosphate kinase NDK-1/NME1 promotes phagocytosis in concert with DYN-1/dynamin.