Figure 1

Introduction to Oncopeltus fasciatus and the workflow for producing a de novo transcriptome assembly. (A) An adult milkweed bug, Oncopeltus fasciatus. (B) Ovaries of adult female. Anterior is up. Oocytes (O) are visible in progressive stages of growth before reaching a common oviduct (Od). Oocytes are cytoplasmically connected to nurse cells (Nc) in the anterior of each ovariole. Scale bar = 1.0 mm. (C-D) The stages of O. fasciatus embryogenesis represented in this transcriptome. Embryos are stained with Sytox Green (Invitrogen) to visualize nuclei. Scale bars = 0.5 mm. (C) Development proceeds from left to right. Anterior is to the left. The cellularized blastoderm forms during the first ~20% of development (~0-24 hours at 28°C), as nuclei reach the surface of the yolk and repeatedly divide. (D) Germ band extension and segmentation occur from ~20-60% of development (~24-72 hours at 28°C). Development proceeds from left to right. Anterior is up. Mn = mandibular segment; Mx = maxillary segment; Lb = labial segment; T1-T3 = leg-bearing thoracic segments 1-3; Ab = abdomen. (E) The flow of information during this de novo transcriptome assembly project. Data files are represented as white boxes within grey boxes that indicate the computer programs used to generate these files. All of the computer programs used are freely available. Ortholog_best_hit_calculator.py and transcriptome_blast_summarizer.py are custom python scripts available at http://www.extavourlab.com/protocols/index.html (see text for details). Photograph in (A) courtesy of David Behl.