Identification, characterisation, and expression profile analysis of the sucrose phosphate synthase gene family in pineapple (<i>Ananas comosus</i>)

Sucrose plays a crucial role in plant growth and development. Sucrose phosphate synthase (SPS, EC 2.4.1.14) is a key rate-limiting enzyme in the sucrose metabolism of plants. To date, the genome-wide identification, characterisation, and expression profile analysis of <i>SPS</i> gene families have been reported in many species but not in pineapple (<i>Ananas comosus</i>). In this study, five <i>SPS</i> genes (<i>AcSPS1–5</i>), which contained sucrose synthase, glucosyltransferase, and SPP-like conserved domains, were identified. The phylogenetic tree indicated that these <i>AcSPS</i> genes were divided into three clades, i.e. A, B, and C. The spatiotemporal expression pattern of <i>AcSPS</i> gene families were first examined in pineapple. Among all tissues, <i>AcSPS2</i> had the highest expression in flesh. Meanwhile, <i>AcSPS2</i> expression was significantly upregulated during fruit development. Furthermore, <i>AcSPS2</i> expression, SPS activity, and sucrose content consistently increased with fruit development. These results may indicate that <i>AcSPS2</i> played a major role in sucrose metabolism during fruit development. <i>AcSPS5</i> was strongly expressed in the peduncle, pericarp, and core. On the basis of its abundant expression, <i>AcSPS5</i> was speculated to play an important role in plant growth.

蔗糖在植物生长发育中发挥关键作用。蔗糖磷酸合酶（SPS, EC 2.4.1.14）是植物蔗糖代谢过程中的关键限速酶。迄今为止，诸多物种的SPS基因家族已被开展全基因组鉴定、特征分析及表达谱解析，但针对菠萝（*Ananas comosus*）的相关研究尚未见报道。本研究共鉴定得到5个SPS基因（AcSPS1~5），其编码蛋白均包含蔗糖合酶、糖基转移酶及SPP-like保守结构域。系统发育树分析显示，这些AcSPS基因可划分为A、B、C三个进化枝。本研究首次对菠萝AcSPS基因家族的时空表达模式进行了检测：在所有检测组织中，AcSPS2在果肉中的表达量最高；同时，AcSPS2的表达量在果实发育过程中显著上调。进一步分析发现，AcSPS2的表达水平、SPS酶活性及蔗糖含量均随果实发育进程持续升高，上述结果表明AcSPS2在果实发育阶段的蔗糖代谢中发挥主要调控作用。AcSPS5在花序梗、果皮及果心中均呈现高表达，结合其丰富的转录本积累，推测AcSPS5在植物生长过程中具有重要功能。

搜集汇总

背景与挑战

背景概述

该数据集通过全基因组分析，首次在菠萝中鉴定了5个蔗糖磷酸合酶基因（AcSPS1-5），并基于系统发育将其分为三个分支。表达谱分析显示AcSPS2在果实发育过程中表达显著上调，与蔗糖积累相关，而AcSPS5在多个组织中高表达，可能参与植物生长调控。