{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T02:24:14Z","timestamp":1778811854126,"version":"3.51.4"},"reference-count":51,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2019,9,18]],"date-time":"2019-09-18T00:00:00Z","timestamp":1568764800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"JSPS KAKENHI","award":["JP19K06339"],"award-info":[{"award-number":["JP19K06339"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS) have been proposed as universal signaling molecules in plant stress responses. There are a growing number of studies suggesting that hydrogen sulfide (H2S) or Reactive Sulfur Species (RSS) are also involved in plant abiotic as well as biotic stress responses. However, it is still a matter of debate as to how plants utilize those RSS in their signaling cascades. Here, we demonstrate that d-cysteine is a novel candidate for bridging our gap in understanding. In the genus of the tiny water-floating fern Azolla, a rapid root abscission occurs in response to a wide variety of environmental stimuli as well as chemical inducers. We tested five H2S chemical donors, Na2S, GYY4137, 5a, 8l, and 8o, and found that 5a showed a significant abscission activity. Root abscission also occurred with the polysulfides Na2S2, Na2S3, and Na2S4. Rapid root abscission comparable to other known chemical inducers was observed in the presence of d-cysteine, whereas l-cysteine showed no effect. We suggest that d-cysteine is a physiologically relevant substrate to induce root abscission in the water fern Azolla.<\/jats:p>","DOI":"10.3390\/antiox8090411","type":"journal-article","created":{"date-parts":[[2019,9,18]],"date-time":"2019-09-18T11:01:15Z","timestamp":1568804475000},"page":"411","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":41,"title":["d-Cysteine-Induced Rapid Root Abscission in the Water Fern Azolla Pinnata: Implications for the Linkage between d-Amino Acid and Reactive Sulfur Species (RSS) in Plant Environmental Responses"],"prefix":"10.3390","volume":"8","author":[{"given":"Hideo","family":"Yamasaki","sequence":"first","affiliation":[{"name":"Faculty of Science, University of the Ryukyus, Okinawa 903-0213, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masahiro P.","family":"Ogura","sequence":"additional","affiliation":[{"name":"Faculty of Science, University of the Ryukyus, Okinawa 903-0213, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Katsumi A.","family":"Kingjoe","sequence":"additional","affiliation":[{"name":"Faculty of Science, University of the Ryukyus, Okinawa 903-0213, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5158-1325","authenticated-orcid":false,"given":"Michael F.","family":"Cohen","sequence":"additional","affiliation":[{"name":"Department of Biology, Sonoma State University, Rohnert Park, CA 94928, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1111\/j.1365-3040.2005.01297.x","article-title":"The NO world for plants: Achieving balance in an open system","volume":"28","author":"Yamasaki","year":"2005","journal-title":"Plant Cell Environ."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1023\/A:1022378621030","article-title":"Involvement of nitric oxide in the mechanism for stomatal opening in Vicia faba leaves","volume":"46","author":"Sakihama","year":"2003","journal-title":"Biol. 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