|
|
|
|
|
|
|
|
|||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
|
Fig. 1. Expression of SPARC transcript and SPARC protein during embryonic development. Transcript and protein expression overlap during gastrulation. (A-N) Wild-type embryos; A, D-G are in situ hybridizations (blue) and B, C, H-N are immunostains. (A) The ventral view of an ES7 embryo shows that SPARC mRNA is expressed by invaginating mesoderm (m) along the ventral midline and the cephalic furrow (cf). (B) Lateral view of an ES8 embryo shows SPARC protein expression (brown) in mesoderm (m), anterior midgut (am) and posterior midgut (pm) primordia. (C) Lateral view of an ES9 embryo shows SPARC protein expression (brown) throughout mesoderm and anterior (am) and posterior (pm) midgut primordia. (D) Lateral view of an ES11 embryo shows SPARC expression (blue) in midgut rudiments as they begin to migrate along the underlying mesoderm. (E) Lateral view of an early ES12 embryo shows SPARC expression at the onset of germ band retraction in growing midgut rudiments and mesoderm. Several neurons are also highlighted at this stage by 22C10 immunostaining (brown, arrow). (F) Dorsal view of an ES12 embryo during germ band retraction. SPARC is observed in migrating midgut rudiment epithelia (blue) and haemocytes (arrows). (G) Dorsal view of an ES13 embryo with fused midgut and haemocytes (arrow) expressing SPARC. (H) Ventral lateral view of haemocytes in an ES13 wild-type embryo. Haemocytes populate the head and begin posterior migration along the ventral nerve cord (VNC) (arrows). (I) The dorsal view of an ES14 embryo shows SPARC-positive haemocytes present throughout the embryo. (J) SPARC immunostains basal laminae around the developing brain (left arrow) and midgut (right arrow) at ES15. (K) Lateral view of an ES17 embryo expressing SPARC in the fat body (arrow) and haemocytes. (L) The same embryo as in K shows SPARC immunostaining in the basal lamina around the midgut (upper arrow), VNC channels and around the VNC (lower arrow). (M,N) Magnified views of an ES14 wild-type embryo immunostained with SPARC antibody (lateral view). (M) Haemocytes (arrows) migrating along the VNC express SPARC. Low to no SPARC immunostaining is observed in haemocyte nuclei. (N) A different focal plane reveals that SPARC colocalizes with VNC channels (arrows) and ventral epidermal (arrowheads) basal laminae. All confocal images are single sections.
|
