The seed-specific transactivator, ABI3, induces oleosin gene expression

Spatiotemporal Seed Development Analysis Provides Insight into Primary Dormancy Induction and Evolution of theLepidium DELAY OF GERMINATION1Genes

“…2 and 7), we captured in type I infructescences stages prior to and at the onset of seed germinability until full premature germination (prior to dormancy induction), and in types II and III infructescences we captured all stages prior to, during, and after the induction of primary dormancy, including the full premature germination stage. To assign these stages to events during seed development and maturation on the molecular level, we analyzed the expression patterns of well-known marker proteins including oleosin (seed storage accumulation), EM6 (seed maturation), and dehydrin (desiccation tolerance; Close et al, 1993;Huang, 1996;Bies et al, 1998;Crowe et al, 2000;Ruuska et al, 2002;Boudet et al, 2006;Siloto et al, 2006;Leprince and Buitink, 2010). Oleosin accumulation during L. papillosum seed development was enhanced with the onset of premature germinability and early maturation in type I and II infructescences.…”

“…kD indicates the protein molecular mass marker ladder. [See online article for color version of this figure.] assign these protein patterns of LepaDOG1 expression to developmental stages within the L. papillosum infructescence, we used monoclonal antibodies directed against oleosin and polyclonal antibodies against EM6 (for Early Met labeled) and dehydrin; the expression abundance of these three proteins is indicative for seed storage accumulation, maturation, and the induction of desiccation tolerance, respectively (Close et al, 1993;Crowe et al, 2000;Boudet et al, 2006;Siloto et al, 2006). In support of the finding that LepaDOG1 is already abundant in immature FOs, abundant LepaDOG1 expression preceded oleosin expression and, therefore, occurs early during seed development already at the filling stage (Fig.…”

“…For immunological detection, the following primary antibodies were used: two different polyclonal antibodies, a-DOG1 1 (Schwab, 2008) and a-DOG1 2 , directed against AtDOG1; a monoclonal antibody, a-oleosine, directed against Arabidopsis D9 oleosin (Crowe et al, 2000;Siloto et al, 2006); a polyclonal antibody, a-EM6, directed against Medicago truncatula Em6 (Boudet et al, 2006); and a polyclonal antibody, a-dehydrin, directed against a wide range of plant species dehydrins (Close et al, 1993). Anti-rabbit IgG-peroxidase conjugate (Sigma) was used for the detection of a-DOG1 1 , a-DOG1 2 , a-EM6, and a-dehydrin, and anti-mouse…”

ABI4 Activates DGAT1 Expression in Arabidopsis Seedlings during Nitrogen Deficiency

“…Hence, ABI3 and ABI5 may also participate in the transcriptional regulation of DGAT1 during N deficiency. In addition, previous studies have shown that ABI3 is required for the regulation of OLEOSIN1 in response to ABA (Crowe et al, 2000). To further determine the roles of ABI transcription factors in TAG accumulation at low N, we examined OLEOSIN1 expression levels in abi3, abi4, and abi5 mutant seedlings.…”

“…In addition to the inhibitory effect on TAG degradation in plant seeds, ABA is also important for TAG accumulation. In response to ABA treatment, ABI3 induces oleosin expression, which is essential for TAG accumulation and oil body stability (Zou et al, 1995;Crowe et al, 2000). In Arabidopsis seedlings, Glc and ABA actively regulate the transcription of ACYL-COENZYME A:DIACYLGLYCEROL ACYLTRANSFERASE1 (DGAT1), which is crucial for TAG biosynthesis (Lu et al, 2003), although the exact molecular mechanism has not been determined.…”