SignificanceUsing strawberry fruit as a model system, we uncover the mechanistic interactions between auxin, gibberellic acid (GA), and abscisic acid (ABA) that regulate the entire process of fruit development. Interlinked regulatory loops control ABA levels during fruit development. During the early stages, auxin/GA turns on a feedback loop to activate the removal of ABA via FveCYP707A4a-dependent catabolism needed for fruit growth. Down-regulation of auxin/GA results in the suppression of the feedback loop and the activation of the ABA biosynthesis-dependent feedforward loop, leading to a steep ABA accumulation for fruit ripening. The interlinked regulatory loops provide a conceptual framework that underlies the connection between the regulation of fruit growth and that of ripening as well as a molecular basis for manipulation of fruit sizes and ripening times.

Oyster is a common food that cause allergy. However, little information is available about its allergens and cross-reactivity. In this study, arginine kinase (AK) was identified as a novel allergen...

In order to reduce the immunoreactivity of sarcoplasmic calcium-binding protein (SCP), site-directed mutations were used to replace key amino acids in the conformational epitopes and calcium-binding sites. The mutant SCPs (mSCPs) were expressed in Escherichia coli, and their immunoreactivities were analyzed using iELISA and basophil activation assays. Furthermore, the structural changes of mSCPs were determined from the circular dichroism spectra. The iELISA results showed that mSCPs could effectively inhibit the binding of wild-type SCP (wtSCP) to sensitive serum, with inhibition rates that reached 90%. Moreover, mSCPs could downregulate the expression levels of CD63 and CD203c on the basophil surface. Compared with wtSCP, the peak values were significantly changed, and the calcium binding ability was impaired, which explained the decline in immunoreactivities of the mSCPs. All of the data confirmed that this approach was effective in reducing the immunoreactivity of SCP and could be applied to other shellfish allergens.

Scallop (Chlamys nobilis) cause IgE mediated food allergy, however, studies on allergens in its musculus are not comprehensive enough. In this connection, the target protein was purified from scallop and...

Mud crab ( Scylla serrata), which is widely consumed, can cause severe allergic symptoms. Eight linear epitopes and seven conformational epitopes of tropomyosin (TM) from S. serrata were identified using phage display. The conformational epitopes were formed based on the coiled-coil structure of TM. Most of the epitopes were located in the regions where primary structures were conserved among crustacean TM. Twelve synthetic peptides were designed according to the epitopes and trypsin-cutting sites of TM, among them, three synthetic peptides (including one linear epitope and two conformational epitopes) were recognized by all of the patient sera using inhibitory dot blotting. A triple-variant (R90A-E164A-Y267A) was constructed based on the critical amino acids of the TM epitope. The IgE-binding activity of the triple-variant was significantly reduced compared with that of native TM. The results of phage display and site-directed mutagenesis offered new information regarding conformational epitopes of TM.