Forty years ago, a high frequency of lethal giant larvae (lgl) alleles in wild populations of Drosophila melanogaster was reported. This locus has been intensively studied for its roles in epithelial polarity, asymmetric neural divisions, and restriction of tissue proliferation. Here, we identify a high frequency of lgl alleles in the Bloomington second chromosome deficiency kit and the University of California at Los Angeles Bruinfly FRT40A-lethal P collection. These unrecognized aberrations confound the use of these workhorse collections for phenotypic screening or genetic mapping. In addition, we determined that independent alleles of insensitive, reported to affect asymmetric cell divisions during sensory organ development, carry lgl deletions that are responsible for the observed phenotypes. Taken together, these results encourage the routine testing of second chromosome stocks for second-site alleles of lgl. 相似文献
Coral Reefs - Epilithic algae are a ubiquitous component of coral reefs. Components of the epilithic algal matrix (EAM) can have a significant influence on coral settlement and benthic feeding by... 相似文献
Coral cover and community structure in the Arabian Gulf have changed considerably in recent decades. Recurrent bleaching events have dramatically reduced the abundance of previously dominant Acropora corals and have given space to other more thermally resistant coral taxa. The loss of Acropora spp. has reduced reef structural complexity and associated biodiversity. Sir Bu Nair Island (SBN) is a nature reserve in the United Arab Emirates that sustains some of the last dense and extensive Acropora stands in the southern Gulf. This study investigated coral recruitment at a southern coral reef on SBN and examined larval dispersal and reef connectivity between SBN and other local and regional reefs through an agent-based model coupled with a 3D hydrodynamic model. Recruitment was surveyed with settlement tiles deployed from April to September 2019. Contrary to other reefs in the Gulf, we found that Acropora is indeed the major coral recruiter settling at SBN reefs, followed by Porites. The models indicate that SBN reefs are mostly self-seeding but also connected to other reefs in the Gulf. SBN can supply coral larvae to the neighbouring islands Siri and Abu Musa, and nearby reefs along with the north-eastern Emirates, Iranian coast and Strait of Hormuz. Findings highlight the importance of SBN to protect remnant populations of the locally almost extinct Acropora in a region where natural coral recovery is increasingly sparse.
We propose a novel technique to measure the small-scale three-dimensional features of a shallow-water coral reef using a small drone equipped with a consumer-grade camera, a handheld GPS and structure from motion (SfM) algorithms. We used a GoPro HERO4 with a modified lens mounted on a DJI Phantom 2 drone (maximum total take-off weight <2 kg) to perform a 10 min flight and collect 306 aerial images with an overlap equal or greater than 90%. We mapped an area of 8380 m2, obtaining as output an ortho-rectified aerial photomosaic and a bathymetric digital elevation model (DEM) with a resolution of 0.78 and 1.56 cm pixel−1, respectively. Through comparison with airborne LiDAR data for the same area, we verified that the location of the ortho-rectified aerial photomosaic is accurate within ~1.4 m. The bathymetric difference between our DEM and the LiDAR dataset is −0.016 ± 0.45 m (1σ). Our results show that it is possible, in conditions of calm waters, low winds and minimal sun glint, to deploy consumer-grade drones as a relatively low-cost and rapid survey technique to produce multispectral and bathymetric data on shallow-water coral reefs. We discuss the utility of such data to monitor temporal changes in topographic complexity of reefs and associated biological processes.
The Wee1 kinase inhibits entry into mitosis by phosphorylation of the Cdc2 kinase. Searching for multicopy suppressors that abolish this inhibition in the fission yeast, we have identified a novel gene, here named wos2, encoding a protein with significant homology to human p23, an Hsp90-associated cochaperone. The deletion mutant has a modest phenotype, being heat-shock sensitive. Using antibodies raised against bacterially produced protein, we determined that Wos2 is very abundant, ubiquitously distributed in the yeast cell, and its expression dropped drastically as cells entered into early stationary phase, indicating that its function is associated with cell proliferation. In proliferating cells, the amount of Wos2 protein was not subjected to cell cycle regulation. However, in vitro assays demonstrated that this Hsp90 cochaperone is potentially regulated by phosphorylation. In addition to suppressing Wee1 activity, overproduction of Wos2 displayed synthetic lethality with Cdc2 mutant proteins, indicating that this Hsp90 cochaperone functionally interacts with Cdc2. The level of Cdc2 protein and its associated H1 kinase activity under synthetic lethal conditions suggested a regulatory role for this Wos2-Cdc2 interaction. Hsp90 complexes are required for CDK regulation; the synergy found between the excess of Wos2 and a deficiency in Hsp90 activity suggests that Wos2 could specifically interfere with the Hsp90-dependent regulation of Cdc2. In vitro analysis indicated that the above genetic interactions could take place by physical association of Wos2 with the single CDK complex of the fission yeast. Expression of the budding yeast p23 protein (encoded by the SBA1 gene) in the fission yeast indicated that Wos2 and Sba1 are functionally exchangeable and therefore that properties described here for Wos2 could be of wide significance in understanding the biological function of cochaperone p23 in eukaryotic cells. 相似文献