TY - JOUR

T1 - Structure of the choanocyte kinetid in the sponge Haliclona sp. (Demospongiae

T2 - Haplosclerida) and its implication for taxonomy and phylogeny of Demospongiae

AU - Pozdnyakov, I. R.

AU - Karpov, S. A.

PY - 2016/12/1

Y1 - 2016/12/1

N2 - Sponges are a group of primitive animals that are of particular interest in terms of evolutionary theory. Molecular and phylogenic studies have revealed the common origin of sponges and Metazoa and the relationship of Metazoa to Choanoflagellata. Comparative studies of the morphology have allowed reconstruction of the structure of ancestors common to Metazoa and Choanoflagellata, as well as for Porifera and other Metazoa. For this purpose, a comparative analysis of phylogenically informative structures, such as the kinetid, is needed. This article presents data on the structure of the choanocyte kinetid in Haliclona sp., which was investigated for the first time. The reconstruction of the kinetid based on ultrathin serial sections shows that it lacks an accessory centriole; it has fibrillar roots despite the basal position of the nucleus; two-to-three triplets of the kinetosome are longer than the others; bundles of lateral microtubules arise from fibrillar roots and reach the cytoplasmic membrane in the region of intercellular contact. The studies of the kinetid in the few representatives of Demospongiae investigated showed the compatibility of the data on the ultrastructure and molecular phylogeny.

AB - Sponges are a group of primitive animals that are of particular interest in terms of evolutionary theory. Molecular and phylogenic studies have revealed the common origin of sponges and Metazoa and the relationship of Metazoa to Choanoflagellata. Comparative studies of the morphology have allowed reconstruction of the structure of ancestors common to Metazoa and Choanoflagellata, as well as for Porifera and other Metazoa. For this purpose, a comparative analysis of phylogenically informative structures, such as the kinetid, is needed. This article presents data on the structure of the choanocyte kinetid in Haliclona sp., which was investigated for the first time. The reconstruction of the kinetid based on ultrathin serial sections shows that it lacks an accessory centriole; it has fibrillar roots despite the basal position of the nucleus; two-to-three triplets of the kinetosome are longer than the others; bundles of lateral microtubules arise from fibrillar roots and reach the cytoplasmic membrane in the region of intercellular contact. The studies of the kinetid in the few representatives of Demospongiae investigated showed the compatibility of the data on the ultrastructure and molecular phylogeny.

KW - choanocytes

KW - choanoflagellates

KW - Demospongiae

KW - Haliclona

KW - kinetid

KW - sponges

UR - http://www.scopus.com/inward/record.url?scp=85012996376&partnerID=8YFLogxK

U2 - 10.1134/S1062359016070153

DO - 10.1134/S1062359016070153

M3 - Article

AN - SCOPUS:85012996376

VL - 43

SP - 595

EP - 601

JO - Biology Bulletin

JF - Biology Bulletin

SN - 1062-3590

IS - 7

ER -