Disease relevance of ACP2

• This difference most likely results from the presence of sufficient substrate pools of C(14) and C(16) acyl-ACPs but a relative lack of C(18) acyl-ACP pools in E. coli to support the activities of the plant fatty acid desaturase [1].
• We have generated transgenic Arabidopsis plants that express high levels of ACP-1, a seed-predominant ACP isoform, in leaf tissue under control of the cauliflower mosaic virus 35S promoter [2].

High impact information on ACP2

• When the FatB1 cDNA encoding a 12:0-ACP TE (Uc FatB1) from California bay, Umbellularia californica (Uc) was expressed in Escherichia coli and in developing oilseeds of the plants Arabidopsis thaliana and Brassica napus, large amounts of laurate (12:0) and small amounts of myristate (14:0) were accumulated [3].
• These results imply that both 12:0- and 14:0-ACP can bind to the two proteins equally well, but in the case of the triple mutant, the hydrolysis of 12:0-ACP is severely impaired [3].
• The A1 gene promoter has been dissected and examined in a transient expression system using the GUS reporter gene [4].
• This 5' intervening sequence appears to be essential to obtain a maximum GUS activity driven by the A1 gene promoter [4].
• Laurate elongation was 85% inhibited by 50 microm cerulenin, an inhibitor of ketoacyl-acyl carrier protein (ACP) synthetase I/II [5].

Biological context of ACP2

• Based upon both their physical separation and a comparison of their sequences, it is suggested that the A4 gene and the A1, A2, and A3 genes constitute two distinct subfamilies within the genome [6].
• Characterization of substrate specificity of plant FatA and FatB acyl-ACP thioesterases [7].
• The deduced amino acid sequence is 51% identical to the lauroyl-ACP thioesterase but only 39% identical to safflower oleoyl-ACP thioesterase [8].
• The results provide evidence that this ACP gene is regulated in a complex manner and is responsive to the array of signals which accompany cell differentiation, and a demand for fatty acids and lipids, during organogenesis [9].
• The deletion of the 5'IVS has much more effect on expression when the promoter activity is under the control of A1 EF-1 alpha upstream sequences than when these upstream sequences were replaced by the 35S enhancer [10].

Anatomical context of ACP2

• Polyribosomal analysis indicated that light also affects the association of ACP transcripts with polysomes, similarly to mRNAs encoding ferredoxin-A [11].
• Together these results demonstrate that plants possess a mechanism for direct activation of FA to ACP in the plastid via an acyl-ACP synthetase encoded by At4g14070 [5].
• Using the GUS reporter gene, transient expression experiments have shown that mutations of upstream cis-acting elements of the A1 promoter, or the deletion of an intron located within the 5' non-coding region, similarly affect expression in dicot or monocot protoplasts [12].

Associations of ACP2 with chemical compounds

• Here, we show that the products of the maize (Zea mays) C2, CHI1, and A1 genes complement Arabidopsis tt4, tt5, and tt3 mutants, restoring the ability of these mutants to accumulate pigments in seed coats and seedlings [13].
• The expression of the maize A1 gene in the flavonoid 3' hydroxylase Arabidopsis tt7 mutant resulted in an increased accumulation of pelargonidin [13].
• The relatively high level of palmitic acid (22 mol%) in cotton seeds may be due in part to a palmitoyl-acyl carrier protein (ACP) thioesterase (PATE), which prefers C16:0-ACP as its substrate [14].
• Pantothenate (vitamin B5) is a water-soluble vitamin essential for the synthesis of CoA and ACP (acyl-carrier protein, cofactors in energy yielding reactions including carbohydrate metabolism and fatty acid synthesis [15].
• The S8 serine, C1A cysteine and A1 aspartic protease families in Arabidopsis [16].

Other interactions of ACP2

• Sequencing of the aspartic proteinase protein purified from Arabidopsis seeds showed that the peptides are derived from two of these genes, A1 and A2 [17].

Analytical, diagnostic and therapeutic context of ACP2

• The combined results, coupled with the sensitivity of acyl-ACP desaturase activity to centrifugation and low salt or detergent suggests low production of unusual monoenes in transgenic plants may be due to the lack of, or incorrect assemble of, a necessary multi-component enzyme association [18].

References