Fig. 4

Experimental approaches in M. lignano.a Metaphase chromosomes (left) and karyotype (right) of M. lignano (2n = 8). Chromosomes were counterstained with DAPI (inverted image). Scale bar 10 µm. b Fluorescence in situ hybridization (FISH) with microdissected DNA probes derived from chromosome 2 (Mli2, green signal) and distal parts of p- and q-arms of chromosome 1 (Mli1dist, red signal) [25]. Scale bar 10 µm. c Whole-mount in situ hybridization showing expression of the CABP7 gene [9] in the ovaries (indicated by arrows). d RNAi knockdown phenotype of the Mlig-Sperm1 gene [45] showing enlarged testes (indicated by arrows). e Composite image of the NL24 transgenic line [9] showing expression of mNeonGreen under the testis-specific promoter of the ELAV4 gene, and mScarlet under the ovary-specific promoter of the CABP7 gene. Note that ELAV4 is expressed in sperm, which is also visible in the seminal vesicle, as well as the female antrum, where it was deposited by another NL24 animal. Scale bars in c–e are 100 µm