him-14 showed strong expression in the syncytial region of the gonad and in embryos but little or no expression in oocytes. him-14 3'UTR reporters showed no increase in oocyte expression in maturing oocytes.
The HIM-17::GFP fusion protein is strongly expressed in the germline and localizes to virtually all germline nuclei in L4 larvae and adult hermaphrodites and males. After fertilization, HIM-17::GFP is detected at low levels in early embryos until about the 16-cell stage.
No or little expression: embryos, L1, L2 and L3 larvae, young adult hermaphrodites, and mixed-stage him-8 mutants that give rise to male-enriched cultures.
Weak expression (<0.5X of control ama-1 expression): embryos, L1, L2, L3, and L4 larvae, young adult hermaphrodites, and mixed-stage him-8 mutants that give rise to male-enriched cultures.
As expected, localization of mkate2::HIM-4 to the pharyngeal basement membrane was observed at the L1 stage. In contrast to the uniform localization on the basement membrane of type IV collagen or nidogen, which are major components of the basement membrane, that of mkate2::HIM-4 was polarized at the anterior part of the pharyngeal basement membrane. A unique polarized localization pattern was also observed in the pharyngeal basement membrane at stage L4. These observations indicate that polarized HIM-4 localization in the anterior part of the pharyngeal BM is maintained throughout the L1-L4 stages. The localization was also observed at the rachis during gonadal development at the L4 stage; this observation was consistent with that of previous reports.
All three gamete types of C. elegans (oocyte, male spermatocyte, and hermaphrodite spermatocyte) show meiosis-specific expression of HIM-3. No protein could be detected in somatic nuclei at any stage of development or in the distal tip nuclei that are undergoing mitotic divisions. A strong signal first appears in the transition zone where HIM-3 is associated with the chromatin of early meiotic prophase nuclei. Localization of HIM-3 becomes more discrete in pachytene and diplotene as the chromosomes synapse and desynapse. The protein remains associated with the chromosomes of oocytes at diakinesis; however, it could no longer be detected in postmeiotic sperm. The antibody identifies the first nuclei that are entering the pachytene stage of meiosis but does not stain the mitotic nuclei.