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Intracellular DNA triggers interferon release during the innate immune response. Cyclic GMP-AMP synthase (cGAS) senses intracellular double-stranded DNA not only in response to viral infection but also under autoimmune conditions. Measuring the levels of cyclic GMP-AMP (cGAMP) as a second messenger of cGAS activation is important to elucidate the physiological and pathological roles of cGAS. Therefore, we generated monoclonal antibodies against cGAMP using hybridoma technology to test antibody specificity and establish methods to detect intracellular cGAMP. The resulting cGAMP-specific antibody enabled the development of a time-resolved fluorescence energy transfer assay with a quantifiable range of 0.1 nM to 100 nM cGAMP. Using this assay, we detected cellular and tissue cGAMP. We confirmed that the cGAMP antibody successfully targeted intracellular cGAMP through immunocytochemical analyses. These results demonstrated that the cGAMP antibody is a powerful tool that allows determining cGAS involvement in autoimmunity and disease pathology at the cell and tissue levels., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Profilin 1 is a central regulator of actin dynamics. Mutations in the gene profilin 1 (PFN1) have very recently been shown to be the cause of a subgroup of amyotrophic lateral sclerosis (ALS). Here, we performed a large screen of US, Nordic, and German familial and sporadic ALS and frontotemporal dementia (FTLD) patients for PFN1 mutations to get further insight into the spectrum and pathogenic relevance of this gene for the complete ALS/FTLD continuum. Four hundred twelve familial and 260 sporadic ALS cases and 16 ALS/FTLD cases from Germany, the Nordic countries, and the United States were screened for PFN1 mutations. Phenotypes of patients carrying PFN1 mutations were studied. In a German ALS family we identified the novel heterozygous PFN1 mutation p.Thr109Met, which was absent in controls. This novel mutation abrogates a phosphorylation site in profilin 1. The recently described p.Gln117Gly sequence variant was found in another familial ALS patient from the United States. The ALS patients with mutations in PFN1 displayed spinal onset motor neuron disease without overt cognitive involvement. PFN1 mutations were absent in patients with motor neuron disease and dementia, and in patients with only FTLD. We provide further evidence that PFN1 mutations can cause ALS as a Mendelian dominant trait. Patients carrying PFN1 mutations reported so far represent the "classic" ALS end of the ALS-FTLD spectrum. The novel p.Thr109Met mutation provides additional proof-of-principle that mutant proteins involved in the regulation of cytoskeletal dynamics can cause motor neuron degeneration. Moreover, this new mutation suggests that fine-tuning of actin polymerization by phosphorylation of profilin 1 might be necessary for motor neuron survival., (Copyright © 2013 Elsevier Inc. All rights reserved.)

We performed a replication study of the 2 genetic variants, rs2814707 on 9p21.2 and rs12608932 on 19p13.3 that are recently reported to be most significantly associated with sporadic amyotrophic lateral sclerosis (ALS) in Caucasians. Both rs12608932 and rs2814707 showed no evidence of association in Japanese and Chinese (rs12608932, combined p = 0.58, odds ratio [OR] = 1.03, 95% confidence interval [CI] 0.93-1.13; rs2814707, combined p = 0.88, OR = 1.10, 95% CI 0.93-1.30). The association of these loci with susceptibility to sporadic ALS is considered negative in East Asians., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Differential screening of a cDNA library constructed using poly(A)(+) RNA from suspension-cultured rice cells treated with jasmonic acid (JA) for 1/2h yielded a cDNA of a gene tentatively named RERJ1 that is upregulated in response to exogenous JA. Northern blot analysis indicated that the RERJ1 mRNA levels peaked at 1/2-1h after the addition of jasmonic acid and then decreased gradually. RERJ1 encodes a transcriptional regulator with a basic helix-loop-helix motif. The phenotypes of transgenic rice plants overexpressing sense or antisense RERJ1 mRNA demonstrated that RERJ1 is involved in the growth inhibition of rice shoots caused by JA. Other biological functions of RERJ1 are discussed from an evolutionary standpoint.