Salicylic acid and jasmonic acid biosynthetic pathways are simultaneously activated in transgenic Arabidopsis expressing the rolB/C gene from Ipomoea batatas.

The Agrobacterium rhizogenes root oncogenic locus (rol) genes interfere with hormone balance by altering their synthesis and/or recognition, giving rise to varied impacts on the physiological characteristics of plants and cell cultures. The homolog of the rolB and rolC genes from Ipomoea batatas, named Ib-rolB/C, similarly induces morphological and physiological alterations in transgenic Arabidopsis thaliana; however, its role in plant hormonal homeostasis has not been previously defined. In this study, we found that external application of salicylic acid (SA) and methyl jasmonate (MeJA) significantly upregulated Ib-rolB/C in detached I. batatas leaves. Furthermore, heterologous expression of Ib-rolB/C in A. thaliana markedly enhanced the accumulation of SA and MeJA, and to a lesser extent, elevated abscisic acid (ABA) levels, through the modulation of genes specific to hormone biosynthesis. Even though the RolB/RolC homolog protein has a notable structural resemblance to the RolB protein from A. rhizogenes, it exhibits a distinct localization pattern, predominantly residing in the cytoplasm and certain discrete subcellular structures, instead of the nucleus. Consequently, the functions of RolB/RolC in both naturally and artificially transgenic plants are linked to changes in the hormonal state of the cells, though the underlying signaling pathways remain to be elucidated.

Tetrodotoxin and its analogues profile in nemertean species from the sea of Japan.

For the first time search for tetrodotoxin (TTX) and its analogues in the extracts of nemerteans using HPLC-MS/MS was performed. TTX analogues were detected in two nemertean species in addition to TTX: 7 analogues were detected in the extract of Cephalothrix simula, 3 analogues - in the extract 11-norTTX of Kulikovia manchenkoi. Presence of 5-deoxyTTX, 11-deoxyTTX, 5,6,11-trideoxyTTX and -6(R)-ol in nemerteans was shown for the first time.

The fatty acid profile changes in marine invertebrate larval cells during cryopreservation.

The development of cryopreservation methods for embryonic cells and larvae of sea animals offers a great potential for marine biotechnology. Larval cells of bivalves and sea urchins were frozen to -196 degrees C using traditional cryoprotectants (Me(2)SO and trehalose) and the cryoprotective mixture developed by us. In addition to Me(2)SO and trehalose, this mixture contained an exogenous lipid extract from mussel tissues and antioxidants. A positive effect of antioxidants (alpha-tocopherol acetate, ascorbic acid or echinochrome, the quinoid pigment of sea urchins) on cell viability became significant only in the presence of exogenous lipids. Antioxidants added to cryoprotective mixtures did not reveal visible cryoprotective activity when used separately. To better understand the mechanism of the protective effect of exogenous lipids on cell membranes of sea animals, a comparative analysis of the fatty acid (FA) composition of total lipids in larval cells before and after freezing was carried out using a gas-liquid chromatography. The results indicate that freezing-thawing has direct effects on the FA composition of major lipid classes in marine invertebrate cells, and these effects can vary depending on the provenance of the cells. We have found that (I) both cell viability and the FA profile of cell lipids after cryopreservation depend on the cryoprotectants used; (II) an amount of saturated, monoenic and polyenic FAs changes significantly after cryopreservation. We assume that the addition of the exogenous lipid extract in form of liposomes could promote a renewal of disturbance areas and prevent from membrane damages during freezing-thawing.