Spindle cell melanoma and desmoplastic melanoma differ clinically in prognosis and therapeutic implications; however, because of partially overlapping histopathological features, diagnostic distinction of spindle cell from desmoplastic melanoma is not always straightforward. A direct comparison of diagnostic and therapeutic biomarkers has not been performed. Meta-review of the literature discloses key clinicopathological differences between spindle cell and desmoplastic melanoma, including immunophenotypes. Using 50 biomarkers available in routine diagnostics, we examined 38 archival cases (n ¼ 16 spindle, 18 desmoplastic, 4 mixed spindle/desmoplastic melanoma). S100 remains as the most reliable routine marker to reach the diagnosis of melanoma in spindle cell and desmoplastic melanoma. We identified nine distinctly labeling markers with spindle cell melanoma showing positivity for laminin, p75, HMB45, c-kit, and MelanA, and desmoplastic melanoma preferentially labeling with collagen IV, trichrome, CD68, and MDM2. On the basis of comparisons of test performance measures, MelanA and trichrome were used to devise a 94% sensitive diagnostic algorithm for the distinction of desmoplastic from spindle cell melanoma. Gene amplification and expression status was assessed for a set of potentially drugable targets (HER2, EGFR, MET, MDM2, TP53, ALK, MYC, FLI-1, and KIT). Fluorescent in situ hybridizations did not reveal a significant number of gene aberrations/rearrangements; however, protein overexpression for at least one of these markers was identified in 35 of 38 cases (92%). In addition, we found BRAF mutations in 31% of spindle cell and 5% of desmoplastic melanoma, with an overall mutation frequency of 16% (n ¼ 6/38). We present the first comprehensive screening study of diagnostic and therapeutic biomarkers in spindle cell and desmoplastic melanoma. The devised algorithm allows diagnostic distinction of desmoplastic from spindle cell melanoma when routine histology is not decisive.

The control of seed germination and seed dormancy are critical for the successful propagation of plant species, and are important agricultural traits. Seed germination is tightly controlled by the balance of gibberellin (GA) and abscisic acid (ABA), and is influenced by environmental factors. The COP9 Signalosome (CSN) is a conserved multi-subunit protein complex that is best known as a regulator of the Cullin-RING family of ubiquitin E3 ligases (CRLs). Multiple viable mutants of the CSN showed poor germination, except for csn5b-1. Detailed analyses showed that csn1-10 has a stronger seed dormancy, while csn5a-1 mutants exhibit retarded seed germination in addition to hyperdormancy. Both csn5a-1 and csn1-10 plants show defects in the timely removal of the germination inhibitors: RGL2, a repressor of GA signaling, and ABI5, an effector of ABA responses. We provide genetic evidence to demonstrate that the germination phenotype of csn1-10 is caused by over-accumulation of RGL2, a substrate of the SCF (CRL1) ubiquitin E3 ligase, while the csn5a-1 phenotype is caused by over-accumulation of RGL2 as well as ABI5. The genetic data are consistent with the hypothesis that CSN5A regulates ABI5 by a mechanism that may not involve CSN1. Transcriptome analyses suggest that CSN1 has a more prominent role than CSN5A during seed maturation, but CSN5A plays a more important role than CSN1 during seed germination, further supporting the functional distinction of these two CSN genes. Our study delineates the molecular targets of the CSN complex in seed germination, and reveals that CSN5 has additional functions in regulating ABI5, thus the ABA signaling pathway.

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Liquid organic hydrogen carriers (LOHCs) represent an attractive concept for storing hydrogen by the hydrogenation of usually aromatic compounds. One of the best investigated LOHCs is N-ethylcarbazole because of its favorable thermodynamic properties. However, its high melting point of 343.1 K could be a major drawback particularly in mobile applications. Therefore, it is desired to decrease the melting point of N-ethylcarbazole without significantly changing favorable properties such as the storage density or the reaction behavior of the carrier compound. To investigate the solid–liquid behavior during hydrogenation, the melting points of pure N-ethylcarbazole derivatives with increasing degree of hydrogenation as well as the liquidus line of the binary mixture of N-ethylcarbazole and N-ethyl-dodecahydro-carbazole were measured. Because of their structural and chemical resemblance binary mixtures consisting of different alkylcarbazole combinations were analyzed regarding their potential for a melting point depression. By the appropriate combination of N-alkylcarbazoles, it is possible to achieve a considerable melting point decrease to 297.1 K.

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