The plastid genomes of peridinin-containing dinoflagellates are highly unusual, possessing very few genes, which are located on small chromosomal elements termed “minicircles”. These minicircles may contain genes, or no recognisable coding information. Transcripts produced from minicircles may undergo unusual processing events, such as the addition of a 3' poly(U) tail. To date, little is known about the genetic or transcriptional diversity of non-coding sequences in peridinin dinoflagellate plastids. These sequences include empty minicircles, and regions of non-coding DNA in coding minicircles. Here, we present an integrated plastid genome and transcriptome for the model peridinin dinoflagellate Amphidinium carterae, identifying a previously undescribed minicircle. We also profile transcripts covering non-coding regions of the psbA and petB/atpA minicircles. We present evidence that antisense transcripts are produced within the A. carterae plastid, but show that these transcripts undergo different end cleavage events from sense transcripts, and do not receive 3' poly(U) tails. The difference in processing events between sense and antisense transcripts may enable the removal of non-coding transcripts from peridinin dinoflagellate plastid transcript pools.

含有peridinin的鞭毛藻的质体基因组非常不寻常，只有很少的基因，这些基因位于称为“微圆”的小染色体元件上。这些小圆圈可能包含基因，或者没有可识别的编码信息。从小圆产生的转录本可能会经历异常的加工事件，例如添加3'poly（U）尾巴。迄今为止，关于peridinin dinoflagellate质体中非编码序列的遗传或转录多样性知之甚少。这些序列包括空的小圆圈，以及编码小圆圈中非编码DNA的区域。在这里，我们为模型peridinin dinoflagellate Amphidinium carterae提供了一个完整的质体基因组和转录组，标识先前未描述的小圆。我们还介绍了覆盖psbA和petB / atpA小圆圈非编码区的转录本。我们目前的证据表明，反义转录物在A. Carterae质体中产生，但显示这些转录物从有义转录物经历不同的末端切割事件，并且不接受3'poly（U）尾巴。有义和反义转录物在处理事件上的差异可以使从peridinin dinoflagellate质体转录物库中去除非编码转录物。