{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T09:16:43Z","timestamp":1790932603858,"version":"4.1.0"},"reference-count":55,"publisher":"The Royal Society","issue":"1695","license":[{"start":{"date-parts":[[2010,5,5]],"date-time":"2010-05-05T00:00:00Z","timestamp":1273017600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/royalsociety.org\/journals\/ethics-policies\/data-sharing-mining\/"}],"content-domain":{"domain":["royalsocietypublishing.org"],"crossmark-restriction":true},"short-container-title":["Proc. R. Soc. B."],"published-print":{"date-parts":[[2010,9,22]]},"abstract":"<jats:p>The seasonal reproductive cycle of photoperiodic rodents is conceptualized as a series of discrete melatonin-dependent neuroendocrine transitions. Least understood is the springtime restoration of responsiveness to winter-like melatonin signals (breaking of refractoriness) that enables animals to once again respond appropriately to winter photoperiods the following year. This has been posited to require many weeks of long days based on studies employing static photoperiods instead of the annual pattern of continually changing photoperiods under which these mechanisms evolved. Maintaining Siberian hamsters under simulated natural photoperiods, we demonstrate that winter refractoriness is broken within six weeks after the spring equinox. We then test whether a history of natural photoperiod exposure can eliminate the requirement for long-day melatonin signalling. Hamsters pinealectomized at the spring equinox and challenged 10 weeks later with winter melatonin infusions exhibited gonadal regression, indicating that refractoriness was broken. A photostimulatory effect on body weight is first observed in the last four weeks of winter. Thus, the seasonal transition to the summer photosensitive phenotype is triggered prior to the equinox without exposure to long days and is thereafter melatonin-independent. Distinctions between photoperiodic and circannual seasonal organization erode with the incorporation in the laboratory of ecologically relevant day length conditions.<\/jats:p>","DOI":"10.1098\/rspb.2010.0396","type":"journal-article","created":{"date-parts":[[2010,5,6]],"date-time":"2010-05-06T00:18:35Z","timestamp":1273105115000},"page":"2867-2874","update-policy":"https:\/\/doi.org\/10.1098\/crossmark-policy","source":"Crossref","is-referenced-by-count":24,"title":["Seasonal regulation of reproduction: altered role of melatonin under naturalistic conditions in hamsters"],"prefix":"10.1098","volume":"277","author":[{"given":"Matthew P.","family":"Butler","sequence":"first","affiliation":[{"name":"Department of Integrative Biology and, University of California, Berkeley, CA 94720"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kevin W.","family":"Turner","sequence":"additional","affiliation":[{"name":"Department of Psychology, University of California, Berkeley, CA 94720"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jin Ho","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Psychology, University of California, Berkeley, CA 94720"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elanor E.","family":"Schoomer","sequence":"additional","affiliation":[{"name":"Department of Psychology, University of California, Berkeley, CA 94720"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irving","family":"Zucker","sequence":"additional","affiliation":[{"name":"Department of Integrative Biology and, University of California, Berkeley, CA 94720"},{"name":"Department of Psychology, University of California, Berkeley, CA 94720"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael R.","family":"Gorman","sequence":"additional","affiliation":[{"name":"Department of Psychology and Center for Chronobiology, University of California, San Diego, CA 92093"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"175","published-online":{"date-parts":[[2010,5,5]]},"reference":[{"key":"e_1_3_2_2_1","doi-asserted-by":"publisher","DOI":"10.1177\/074873040001500206"},{"key":"e_1_3_2_3_1","doi-asserted-by":"publisher","DOI":"10.1016\/0006-8993(92)90172-6"},{"key":"e_1_3_2_4_1","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod63.3.769"},{"key":"e_1_3_2_5_1","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod24.3.568"},{"key":"e_1_3_2_6_1","doi-asserted-by":"publisher","DOI":"10.1002\/jez.544"},{"key":"e_1_3_2_7_1","first-page":"R402","article-title":"Simulated natural day lengths synchronize seasonal rhythms of asynchronously born male Siberian hamsters","volume":"293","author":"Butler M. P.","year":"2007","journal-title":"Am. J. Physiol."},{"key":"e_1_3_2_8_1","first-page":"R413","article-title":"Timing of puberty and synchronization of seasonal rhythms by simulated natural photoperiods in female Siberian hamsters","volume":"293","author":"Butler M. P.","year":"2007","journal-title":"Am. J. Physiol."},{"key":"e_1_3_2_9_1","doi-asserted-by":"publisher","DOI":"10.1177\/0748730408317135"},{"key":"e_1_3_2_10_1","doi-asserted-by":"publisher","DOI":"10.1210\/endo-113-4-1261"},{"key":"e_1_3_2_11_1","doi-asserted-by":"publisher","DOI":"10.1210\/endo-116-1-424"},{"key":"e_1_3_2_12_1","doi-asserted-by":"publisher","DOI":"10.1210\/en.2008-0834"},{"key":"e_1_3_2_13_1","first-page":"2339","article-title":"Circadian rhythms and photoperiodic time measurement in mammals","volume":"35","author":"Elliott J. A.","year":"1976","journal-title":"Fed. Proc."},{"key":"e_1_3_2_14_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF00191713"},{"key":"e_1_3_2_15_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.111140398"},{"key":"e_1_3_2_16_1","doi-asserted-by":"publisher","DOI":"10.1177\/074873001129001980"},{"key":"e_1_3_2_17_1","doi-asserted-by":"publisher","DOI":"10.1177\/074873000129001503"},{"key":"e_1_3_2_18_1","first-page":"107","volume-title":"Chronobiology: biological timekeeping","author":"Goldman B. D.","year":"2004"},{"key":"e_1_3_2_19_1","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod53.1.110"},{"key":"e_1_3_2_20_1","first-page":"R1613","article-title":"A plastic interval timer synchronizes pubertal development of summer- and fall-born hamsters","volume":"281","author":"Gorman M. R.","year":"2001","journal-title":"Am. J. Physiol."},{"key":"e_1_3_2_21_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2826.2003.01104.x"},{"key":"e_1_3_2_22_1","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod53.1.116"},{"key":"e_1_3_2_23_1","first-page":"R887","article-title":"Environmental induction of photononresponsiveness in the Siberian hamster. Phodopus sungorus.","volume":"272","author":"Gorman M. R.","year":"1997","journal-title":"Am. J. Physiol."},{"key":"e_1_3_2_24_1","first-page":"195","volume-title":"Biological clocks, mechanisms and applications","author":"Gorman M. R.","year":"1998"},{"key":"e_1_3_2_25_1","doi-asserted-by":"crossref","first-page":"481","DOI":"10.1007\/978-1-4615-1201-1_19","volume-title":"Circadian clocks, handbook of behavioral neurobiology, volume 12","author":"Gorman M. R.","year":"2001"},{"key":"e_1_3_2_26_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cub.2008.06.076"},{"key":"e_1_3_2_27_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cub.2008.07.040"},{"key":"e_1_3_2_28_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cub.2005.06.010"},{"key":"e_1_3_2_29_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF00694233"},{"key":"e_1_3_2_30_1","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-642-68651-1_33"},{"key":"e_1_3_2_31_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2826.2003.00966.x"},{"key":"e_1_3_2_32_1","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod51.5.1046"},{"key":"e_1_3_2_33_1","doi-asserted-by":"publisher","DOI":"10.1177\/074873049100600403"},{"key":"e_1_3_2_34_1","doi-asserted-by":"publisher","DOI":"10.1080\/07420520500464452"},{"key":"e_1_3_2_35_1","doi-asserted-by":"publisher","DOI":"10.1677\/joe.0.1790001"},{"key":"e_1_3_2_36_1","doi-asserted-by":"publisher","DOI":"10.1210\/en.2005-0132"},{"key":"e_1_3_2_37_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1600-079X.1987.tb00843.x"},{"key":"e_1_3_2_38_1","doi-asserted-by":"publisher","DOI":"10.1210\/endo.136.1.7828525"},{"key":"e_1_3_2_39_1","doi-asserted-by":"publisher","DOI":"10.1210\/endo-128-3-1337"},{"key":"e_1_3_2_40_1","doi-asserted-by":"publisher","DOI":"10.1177\/0748730406292315"},{"key":"e_1_3_2_41_1","doi-asserted-by":"publisher","DOI":"10.1098\/rstb.2007.2143"},{"key":"e_1_3_2_42_1","doi-asserted-by":"publisher","DOI":"10.1177\/074873099129000452"},{"key":"e_1_3_2_43_1","first-page":"R1041","article-title":"Enhanced reproductive responses to melatonin in juvenile Siberian hamsters","volume":"271","author":"Prendergast B. J.","year":"1996","journal-title":"Am. J. Physiol."},{"key":"e_1_3_2_44_1","doi-asserted-by":"publisher","DOI":"10.1086\/393989"},{"key":"e_1_3_2_45_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.232490799"},{"key":"e_1_3_2_46_1","doi-asserted-by":"publisher","DOI":"10.1016\/B978-008088783-8.00014-0"},{"key":"e_1_3_2_47_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF00612490"},{"key":"e_1_3_2_48_1","first-page":"R670","article-title":"Circadian characteristics of Djungarian hamsters: effects of photoperiodic pretreatment and artificial selection","volume":"261","author":"Puchalski W.","year":"1991","journal-title":"Am. J. Physiol."},{"key":"e_1_3_2_49_1","doi-asserted-by":"publisher","DOI":"10.1016\/0016-6480(69)90162-2"},{"key":"e_1_3_2_50_1","doi-asserted-by":"publisher","DOI":"10.1002\/jez.1402020110"},{"key":"e_1_3_2_51_1","doi-asserted-by":"publisher","DOI":"10.1095\/biolreprod34.4.664"},{"key":"e_1_3_2_52_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2826.2006.01511.x"},{"key":"e_1_3_2_53_1","doi-asserted-by":"publisher","DOI":"10.1177\/0748730408325233"},{"key":"e_1_3_2_54_1","doi-asserted-by":"publisher","DOI":"10.1210\/en.2003-1593"},{"key":"e_1_3_2_55_1","doi-asserted-by":"publisher","DOI":"10.1210\/endo-114-2-664"},{"key":"e_1_3_2_56_1","doi-asserted-by":"crossref","first-page":"509","DOI":"10.1007\/978-1-4615-1201-1_20","volume-title":"Circadian clocks, volume 12, Handbook of behavioral neurobiology","author":"Zucker I.","year":"2001"}],"container-title":["Proceedings of the Royal Society B: Biological Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/royalsocietypublishing.org\/doi\/pdf\/10.1098\/rspb.2010.0396","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/royalsocietypublishing.org\/doi\/full-xml\/10.1098\/rspb.2010.0396","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/royalsocietypublishing.org\/doi\/pdf\/10.1098\/rspb.2010.0396","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,2,21]],"date-time":"2021-02-21T06:33:58Z","timestamp":1613889238000},"score":1,"resource":{"primary":{"URL":"https:\/\/royalsocietypublishing.org\/doi\/10.1098\/rspb.2010.0396"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,5,5]]},"references-count":55,"journal-issue":{"issue":"1695","published-print":{"date-parts":[[2010,9,22]]}},"alternative-id":["10.1098\/rspb.2010.0396"],"URL":"https:\/\/doi.org\/10.1098\/rspb.2010.0396","relation":{},"ISSN":["0962-8452","1471-2954"],"issn-type":[{"value":"0962-8452","type":"print"},{"value":"1471-2954","type":"electronic"}],"subject":[],"published":{"date-parts":[[2010,5,5]]},"assertion":[{"value":"2010-02-25","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2010-04-15","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2010-05-05","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}