Veremeichik G.N., Shkryl Y.N., Bulgakov V.P., Shedko S.V., Kozhemyako V.B., Kovalchuk S.N., Krasokhin V.B., Zhuravlev Y.N., Kulchin Y.N.
В журнале Marine Biotechnology
Год: 2011 Том: 13 Страницы: 810-819
Silicatein genes are involved in spicule formation in demosponges (Demospongiae: Porifera). However, numerous attempts to isolate silicatein genes from glass sponges (Hexactinellida: Porifera) resulted in a limited success. In the present investigation, we performed analysis of potential silicatein/cathepsin transcripts in three different species of glass sponges (Pheronema raphanus, Aulosaccus sp. and Bathydorus sp.). In total, 472 clones of such transcripts have been analyzed. Most of them represent cathepsin transcripts and only three clones have been found to represent transcripts, which can be related to silicateins. Silicatein transcripts were identified in Aulosaccus sp. (Hexactinellida; Lyssacinosida; Rosselidae), and the corresponding gene was called AuSil-Hexa. Expression of AuSil-Hexa in Aulosaccus sp. was confirmed by real-time PCR. Comparative sequence analysis indicates high sequence identity of the Aulosaccus sp. silicatein with demosponge silicateins described previously. A phylogenetic analysis indicates that the AuSil-Hexa protein belongs to silicateins. However, the AuSil-Hexa protein contains a catalytic cysteine instead of the conventional serine.