Calcium/calmodulin-dependent kinases are involved in growth, thermotolerance, oxidative stress survival, and fertility i
- PDF / 879,675 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 59 Downloads / 180 Views
Short Communication
Calcium/calmodulin‑dependent kinases are involved in growth, thermotolerance, oxidative stress survival, and fertility in Neurospora crassa Ravi Kumar · Ranjan Tamuli
Received: 24 May 2013 / Revised: 3 February 2014 / Accepted: 10 February 2014 © Springer-Verlag Berlin Heidelberg 2014
Abstract Calcium/calmodulin-dependent kinases (Ca2+/CaMKs) are Ser/Thr protein kinases that respond to change in cytosolic free Ca2+ ([Ca2+]c) and play multiple cellular roles in organisms ranging from fungi to humans. In the filamentous fungus Neurospora crassa, four Ca2+/ CaM-dependent kinases, Ca2+/CaMK-1 to 4, are encoded by the genes NCU09123, NCU02283, NCU06177, and NCU09212, respectively. We found that camk-1 and camk2 are essential for full fertility in N. crassa. The survival of Δcamk-2 mutant was increased in induced thermotolerance and oxidative stress conditions. In addition, the Δcamk-1 Δcamk-2, Δcamk-4 Δcamk-2, and Δcamk-3 Δcamk-2 double mutants display slow growth phenotype, reduced aerial hyphae, decreased thermotolerance, and increased sensitivity to oxidative stress, revealing the genetic interactions among these kinases. Therefore, Ca2+/CaMKs are involved in growth, thermotolerance, oxidative stress tolerance, and fertility in N. crassa. Keywords Calcium/calmodulin-dependent kinases · Fertility · Growth · Neurospora crassa · Oxidative stress · Thermotolerance
Communicated by Olaf Kniemeyer. Electronic supplementary material The online version of this article (doi:10.1007/s00203-014-0966-2) contains supplementary material, which is available to authorized users. R. Kumar · R. Tamuli (*) Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781 039, India e-mail: [email protected]; [email protected]
Introduction Calcium ion (Ca2+) is a ubiquitous second-messenger molecule that impacts almost all cellular processes in eukaryotes (Gadd 1994; Berridge et al. 1998). The resting concentration of cytosolic free Ca2+ ([Ca2+]c) is ~100 nm, whereas Ca2+ in the extracellular fluid is ~10−3 M (Chin and Means 2000). The Ca2+-mediated signal transduction process typically involves transient increase in [Ca2+]c due to entry of extracellular Ca2+ or release of Ca2+ from internal stores (Chin and Means 2000). The increased [Ca2+]c is detected by multiple Ca2+-sensing proteins triggering a versatile Ca2+ signaling process. A ubiquitous Ca2+-sensing protein called calmodulin (CaM), which contains four EF-hand Ca2+-binding motifs, undergoes conformational change upon Ca2+-binding, and the resulting Ca2+/CaM complex regulates a number of effector proteins including Ca2+/CaM-dependent protein kinases (Ca2+/CaMKs) that are serine/threonine (Ser/Thr) protein kinases (Chin and Means 2000; Soderling and Stull 2001). The general domain organization of Ca2+/CaMKs includes a highly conserved N-terminal catalytic domain and a C-terminal regulatory region consisting of overlapping autoinhibitory and Ca2+/CaM-binding domains (Swulius and Waxham 2008; Tamuli et al. 2011). Binding of Ca
Data Loading...
