Search

Anther cuticle and pollen exine are two physical barriers protecting plant reproductive cells against environmental stresses; defects in either often cause male sterility. Here, we report the characterization of a male-sterile mutant irregular pollen exine2 ( ipe2 ) of maize ( Zea mays ), which displays shrunken anthers and no starch accumulation in mature pollen grains. We cloned the causal gene IPE2 and confirmed its role in male fertility in maize with a set of complementary experiments. IPE2 is specifically expressed in maize developing anthers during stages 8 to 9 and encodes an endoplasmic-reticulum-localized GDSL lipase. Dysfunction of IPE2 resulted in delayed degeneration of tapetum and middle layer, leading to defective formation of anther cuticle and pollen exine, and complete male sterility. Aliphatic metabolism was greatly altered, with the contents of lipid constituents, especially C16/C18 fatty acids and their derivatives, significantly reduced in ipe2 developing anthers. Our study elucidates GDSL function in anther and pollen development and provides a promising genetic resource for breeding hybrid maize., (© 2020 American Society of Plant Biologists. All Rights Reserved.)

Background: A number of meta-analyses have been carried out to evaluate the effects of minimally invasive surgery (MIS) versus open surgery (OS) for acute Achilles tendon rupture. However, discordant findings were seen in these meta-analyses. The present study, performing a systematic review of overlapping meta-analyses regarding MIS versus OS of acute Achilles tendon rupture, aimed to assist decision-makers interpret and choose among conflicting meta-analyses, as well as to offer treatment recommendations based on current best evidence., Methods: The literature search was performed to identify systematic reviews comparing MIS with OS for Achilles tendon rupture. Meta-analyses only comprising randomized controlled trials (RCTs) were included. Two authors individually evaluated the quality of meta-analysis and extracted data. The Jadad decision algorithm was conducted to ascertain which meta-analysis offered the best evidence., Results: A total of four meta-analyses was included. All these meta-analyses comprised RCTs or quasi-RCTs and were determined as Level-II evidence. The scores of the Assessment of Multiple Systematic Reviews (AMSTAR) ranged from 7 to 10 (median 9.5). The Jadad algorithm indicated that the best meta-analysis should be chosen according to the search strategies and application of selection. A high-quality meta-analysis with more RCTs was chosen, which suggested that there was no statistically significant difference between MIS and OS regarding rerupture rate, tissue adhesion, sural nerve injury, deep infection, and deep vein thrombosis. However, MIS could decrease superficial infection rate, and had a better patient satisfaction for good to excellent outcomes in comparison to OS., Conclusions: Based on the best available evidence, MIS may be superior to OS for treating acute Achilles tendon rupture. However, due to some limitations, this should be cautiously interpreted, and further high-quality studies are needed.