Fos-like antigens (Fosl) including Fosl1 and Fosl2 exclusively heterodimerize with Jun members to form AP-1 complex, thereby participating in various cellular progresses including cell cycle regulation. However, expression patterns of these two genes during embryonic development remains largely unknown. In the present study, both temporal and spatial expression patterns of fosl1 and fosl2 were examined during embryonic development of Xenopus tropicalis. Real-time quantitative PCR results showed that the expression of the two genes was increased from stage 2 to stage 42. However, expression level of fosl1 is much higher than that of fosl2 at stage 42. Whole-mount in situ hybridization showed that fosl1 was expressed in eyes, branchial arch, notochord, otic vesicle, and liver. However, fosl2 was expressed in lung primordium from stage 34 to stage 38, in addition to the moderate expression in eyes and branchial arch at stage 42. Thus, the developmental expression patterns of these two fosl genes is different in Xenopus embryos. These results provide a basis for further functional study of these two genes.

包括Fosl1和Fosl2在内的Fos样抗原（Fosl）仅与Jun成员异源二聚形成AP-1复合物，从而参与各种细胞进程，包括细胞周期调控。但是，这两个基因在胚胎发育过程中的表达模式仍然很大程度上未知。在本研究中，在非洲爪蟾的胚胎发育过程中检查了fosl1和fosl2的时空表达模式。显示实时定量PCR的结果，这两个基因的表达，从第2阶段上升到阶段42。然而，表达水平FOSL1比的高得多的FOSL2在阶段42整个安装在原位杂交表明，fosl1在眼，arch弓，脊索，耳囊和肝脏中表达。但是，除了在第42阶段在眼睛和分支弓中的适度表达外，从第34阶段到第38阶段，fosl2在肺原基中表达。因此，这两个fosl基因在非洲爪蟾胚胎中的发育表达模式是不同的。这些结果为进一步研究这两个基因提供了基础。