In this study the responses of the chloroplast transcriptional apparatus in barley (Hordeum vulgare L. cv. Carina) primary foliage leaves were examined during and after interruption of the light/dark growth regime by a two‐day period of light deprivation on days 10 and 11 after sowing.Run‐on transcript assays and northern blot analyses showed that transcripts in chloroplasts can be divided into at least three groups that differ in their levels during the dark period and in the kinetics of their resynthesis during the reillumination phase. Group I transcripts (rbcL, psaA,B, atpB) show decreased expression as well as reduced transcript accumulation during the dark period both of which are restored within 32 h after reillumination of the plants. Group II (psbA, psbD) and group III (16S rRNA, trnE) transcripts show a delayed or no detectable response to prolonged darkness at the transcript level. While group II transcription does not change significantly upon reillumination, transcription of group III genes increases substantially above the initial value within a very short time after retransfer into light.Changes in gene specificity of the transcriptional apparatus are accompanied by a changing sensitivity of the chloroplast transcriptional apparatus towards the transcription inhibitor tagetitoxin. The strongest inhibitory effect of tagetitoxin could be observed in leaves recovering from the dark‐induced stress situation.

Krause, K., Falk, J., Humbeck, K., & Krupinska, K. (1998). Responses of the transcriptional apparatus of barley chloroplasts to a prolonged dark period and to subsequent reillumination. Physiologia Plantarum, 104(2), 143–152. Portico.