Transcriptomic analysis in each reproductive cell of green seaweed Ulva

The green seaweed Ulva belongs to class Ulvophyceae and primarily exists in marine habitats. In the life cycle of Ulva, each gametophyte of mating type minus and mating type plus releases biflagellate gametes, and then a mating type minus gamete conjugates with a mating type plus gamete and followed by development into a sporophyte. The sporophytes generate and release quadriflagellate meiospores through meiosis, and the released meiospores develop into genetically separated mating type minus or mating type plus gametophytes. Instead of the ordinary sexual life cycle, several Ulva species have asexual life cycles that occur without sexual reproduction via meiosis and conjugation. There are two types of asexual cycles, one via biflagellate zoids, and the other via quadriflagellate zoids. The biflagellate and quadriflagellate zoids develop directly into asexual thalli. To understand the molecular basis of the morphological and biological differences between gametes, asexual biflagellate and quadriflagellate zoids, we conducted transcriptome analysis.