Oocytes of a single individual of Halocynthia roretzi (Aomori, Japan) were fertilized by sperms of an another single individual and development was followed microscopically. Embryos were snapfrozen in liquid nitrogen at the appropriate stage and kept at -80°C. Total RNA was prepared with the AGPC method and the quality was checked with the Bioanalyzer, most samples had a RIN value of higher than 9. Strand specific libraries were constructed and the sequencing (50PE) was performed with Illumina HiSeq 2000 technology (BGI, Hong Kong, China).

Vegetal view of a 64-cell stage wild type embryo probed for HrTRP expression.

Original Annotation :
No expression detected.

Vegetal view of a 110-cell stage wild type embryo probed for HrTRP expression.

Original Annotation :
HrTRP expression was detected in notochord and some cells of neural plate.

Vegetal view of a mid gastrula wild type embryo probed for HrTRP expression.

Original Annotation :
HrTRP expression was detected in some notochord lineage cells. The expression also appears in the a8.25 cell pair, pigment lineage cells in the eighth generation, and also in the a8.17 and a8.19 pairs.

Vegetal view of a mid gastrula wild type embryo probed for HrTRP expression.

Original Annotation :
In the mid-gastrula stage, expression persists in the six a-line cells and appears transiently in the adjacent four b-line cells which give rise to muscle, epidermis, brain stem, endodermal-strand and spinal cord, but is barely detectable in other cells.

Vegetal view of a late gastrula wild type embryo probed for HrTRP expression.

Original Annotation :
HrTRP expression was detected in neural plate, more precisely in row III and row IV of neural plate.

Comments :
There are also weak signals at either side of the blastopore, and the signals sometimes persist by the late neurula stage.

Dorsal view of an early neurula probed for HrTRP expression.

Original Annotation :
HrTRP expression was detected in 12-a line cells constituting the anterior part of the neural plate, which became intense in a9.49 cells.

Dorsal view of the anterior region of an early neurula stage embryo probed for HrTRP expression.

Original Annotation :
Expression of the HrTRP gene is detected in 12 a-line cells comprising the anterior part of the neural tube, and the most intense expression is found in the a9.49 pair (white arrowheads).

Dorsal view of a mid neurula probed for HrTRP expression.

Original Annotation :
Signals become intense exclusively in the a9.49 pair, the bilateral pigment precursor cells in the ninth generation, and start to fade in the other ten a-line cells.

Dorsal view of a late neurula probed for HrTRP expression.

Original Annotation :
At this stage the expression of this gene becomes very intense in a10.97 and a10.98 cell pairs, derived from the final ninth division of the a9.49 cells.

A dorsal view of an early tailbud stage embryo probed for HrTRP expression.

Original Annotation :
HrTRP gene expression is detected in a10.97 and a10.98 aligning along the dorsal midline of the neural tube.

Aniseed Annotation :
According to lineage information, a10.97 and a10.98 progeny is the dorsal anterior sensory vesicle at early tailbud stage.

A lateral view of a mid tailbud I probed for HrTRP expression.

Original Annotation :
Expression is detected in the progeny of a10.97 and a10.98 from the dorsal midline of row IV of the neural tube.

Aniseed Annotation :
According to lineage information, a10.97 and a10.98 progeny is the dorsal anterior sensory vesicle at mid tailbud I stage.