The male gonad of the marine nematode Enoplus: No single distal tip cell but multiple uniform epithelial cells

• DOI: 10.15298/invertzool.11.2.07
• Publication Date: 2018-09-25T14:27:57Z
• Authors: V. V. Yushin; A. G. Afanasiev-G...; V. V. Malakhov
• Keywords: 0301 basic medicine; 03 medical and health sciences

The distal tip cell (DTC) is a large single located at the apex of nematode gonadal arms.It well investigated in Caenorhabditis elegans Maupas, 1900 and described many other species class Chromadorea.It has been obtained convincing evidence that C. DTC plays an essential role development gonads regulation gametogenesis.We have studied fine structure part testis free living marine nematodes Enoplus.TEM observations revealed absence specialized testes E. michaelseni (Linstow, 1896) brevis Bastian, 1865.The both lined with numerous uniform epithelial cells (TEC) forming uninterrupted epithelium adjacent to basal lamina.Besides that, TEC form long outgrowths protruding deeply into between spermatogonia.Unlike elegans, multiple Enoplus spp.show hardly any signs synthetic activity.They possess neither nucleoli nor rough endoplasmic reticulum their cytoplasm, but contain thick bundles filaments giving no for glandular or hormonal function.The multicellular spp.complements plesiomorphic characters enoplid (e.g.indeterminate early development, constancy, regeneration ability, preservation nuclear envelope spermatozoa) may be considered as additional position order Enoplida within phylum Nematoda.