scholarly journals Interaction Between Maternal Effect and Zygotic Effect Mutations During Maize Seed Development

Genetics ◽  
2001 ◽  
Vol 159 (1) ◽  
pp. 303-315 ◽  
Author(s):  
Matthew M S Evans ◽  
Jerry L Kermicle

Abstract Double fertilization of the embryo sac by the two sperm cells of a pollen grain initiates seed development. Proper development of the seed depends not only on the action of genes from the resulting embryo and endosperm, but also on maternal genes acting at two stages. Mutations with both sporophytic maternal effects and gametophytic maternal effects have been identified. A new maternal effect mutation in maize, maternal effect lethal1 (mel1), causes the production of defective seed from mutant female gametophytes. It shows reduced pollen transmission, suggesting a requirement in the male gametophyte, but has no paternal effect on seed development. Interestingly, the defective kernel phenotype of mel1 is conditioned only in seeds that inherit mel1 maternally and are homozygous for the recessive allele (endogenous to the W22 inbred line) of either of two genes, sporophyte enhancer of mel1 (snm1) or snm2, suggesting redundancy between maternally and zygotically required genes. Both mel1 and snm1 map to the short arm of chromosome 2, and snm2 maps to the long arm of chromosome 10. The mode of action of mel1 and the relationship between mel1 and snm1 and snm2 are discussed.

Genetics ◽  
1973 ◽  
Vol 73 (1) ◽  
pp. 73-86
Author(s):  
Arthur P Mange ◽  
L Sandler

ABSTRACT Two deficiencies for, and a dominant enhancer of, the second chromosome maternal effect mutant, "daughterless" (da), were induced with X-irradiation. Their properties were studied with respect to both da and the linked maternal effect mutant, "abnormal oocyte" (abo), with the following conclusions. (1) The most probable map positions of da and abo are: J–½–da–2½–abo, where J is a dominant marker located at 41 on the standard map. (2) The da locus is in bands 31CD-F on the polytene chromosome map; abo is to the right of 32A. (3) Because homozygous da individuals survive while individuals carrying da and a deficiency for da are lethal, it is concluded that da is hypomorphic. (4) From a weak da-like maternal effect in heterozygous da females induced by an "Enhancer of da," we have confirmed a previous report that (a) the amount of sex chromosome heterochromatin contributed by the father can influence the severity of the da maternal effect, and (b) the sex chromosome heterochromatin which influences the da effect is different from that which influences the abo effect. (5) The possibility that da and abo are in a special region of chromosome 2 concerned with the regulation of sex chromosome heterochromatin is strengthened by the observation that the Enhancer of da appears to rescue abnormal eggs produced by homozygous abo mothers. (6) The Enhancer of da is a translocation between chromosomes 2 and 3 with the second chromosome breakpoint in the basal heterochromatin; because the enhancing effect maps in this region of chromosome 2, it is possible that autosomal, as well as sex chromosomal, heterochromatin interacts with da and abo.


2019 ◽  
Vol 20 (2) ◽  
pp. 420 ◽  
Author(s):  
Ren Zheng ◽  
Shun Su ◽  
Hui Xiao ◽  
Hui Tian

Pollen is the male gametophyte of higher plants. Its major function is to deliver sperm cells to the ovule to ensure successful fertilization. During this process, many interactions occur among pollen tubes and pistil cells and tissues, and calcium ion (Ca2+) dynamics mediate these interactions among cells to ensure that pollen reaches the embryo sac. Although the precise functions of Ca2+ dynamics in the cells are unknown, we can speculate about its roles on the basis of its spatial and temporal characteristics during these interactions. The results of many studies indicate that calcium is a critical element that is strongly related to pollen germination and pollen tube growth.


2017 ◽  
Vol 92 (6) ◽  
pp. 1143-1156 ◽  
Author(s):  
Wenwei Xiong ◽  
Chunlei Wang ◽  
Xiangbo Zhang ◽  
Qinghua Yang ◽  
Ruixin Shao ◽  
...  

2017 ◽  
Vol 174 (2) ◽  
pp. 1127-1138 ◽  
Author(s):  
Yan-Zhuo Yang ◽  
Shuo Ding ◽  
Yong Wang ◽  
Cui-Ling Li ◽  
Yun Shen ◽  
...  

2014 ◽  
Vol 18 (1) ◽  
pp. 22-35 ◽  
Author(s):  
Domenico Celenza ◽  
Fabrizio Rossi

Purpose – The aim of this paper is to investigate the relationship between corporate performance and Value Added Intellectual Coefficient (VAICTM) on the one hand, and the relationship between the variations in market value and the variations in VAIC on the other hand. Design/methodology/approach – Starting from the VAIC model, 23 Italian listed companies were examined with the aim of investigating the relationship between VAIC and the performance of the firms in the sample. The analysis was divided into two stages. In the first stage, eight models of linear regression were estimated to verify the presence of a positive and statistically significant relationship between M/BV and VAIC and between accounting performance indicators (ROE, ROI, ROS) and the VAIC. In the second stage, six other models were tested, considering as an independent variable the variations in VAIC and the variations in profitability indicators. Findings – The outcomes of the application stress the importance of VAIC in the explanation of the variations in MV and its role as “additional coefficient” in the analysis of equity performance. Originality/value – This methodology highlights some very interesting aspects. In particular, whereas the relationship between M/BV and VAIC and between profitability indicators (ROI, ROE, ROS) and VAIC is statistically insignificant, the subsequent analysis highlights the importance of VAIC as a variable capable of increasing the explanatory power of the regression in a cross-sectional perspective.


Genetics ◽  
1995 ◽  
Vol 140 (1) ◽  
pp. 183-192
Author(s):  
A R Lohe ◽  
D A Lidholm ◽  
D L Hartl

Abstract The baseline rate of spontaneous integration of the autonomous mariner element Mos1 into the germline of Drosophila melanogaster is estimated as 16 +/- 5% (mean +/- SE) among fertile G0 flies. However, the transformation rate is reduced approximately 20-fold in Mos1 constructs with exogenous DNA in the size range 5-12 kb inserted into the SacI site. To provide alternative Mos1 helper plasmids for transformation experiments, two types of Mos1-promoter fusions were constructed: hsp-70:Mos1 and hsp26-Sgs3:Mos1. The former has the Mos1 coding region driven by the hsp70 heat-shock promoter; the latter has it driven by the basal Sgs3 promoter under the control of the hsp26 female-germline specific transcriptional regulator. When introduced into D. melanogaster by P-element-mediated germline transformation, these elements are unable to transpose or excise in the presence of autonomous Mos1-related elements (they are "marooned") because the 5' inverted repeat of Mos1 is missing. As expected, the hsp26-Sgs3:Mos1 fusions exhibit a significantly greater rate of germline excision of a target mariner element than do the hsp70:Mos1 fusions. Unexpectedly, the rate of excision of target mariner elements induced by hsp26-Sgs3:Mos1 is the same in the male germline as in the female germline. Both hsp:Mos1 fusions show strong germline expression and a maternal effect of the mariner transposase. A significant grand-maternal effect of the hsp:Mos1 fusions was also detected as a result of a maternal effect on the germline of the F1 progeny. Among flies carrying the promoter fusions inherited maternally, about three-quarters of the overall rate of germline excision derives from the direct genotypic effect and about one-quarter results from the grand-maternal effect. Despite the strong somatic expression of the hsp:Mos1 fusions, mariner transformants carrying a white+ reporter gene at the SacI site remained stable in the soma.


2022 ◽  
Vol 6 (6) ◽  
Author(s):  
Asri Silvana Naiu ◽  
Nikmawatisusanti Yusuf ◽  
Yusnina Hudongi

This study aimed to analyze changes in the number of molds and the level of panelist acceptance of K. alvarezii jelly candy packaged using gelatin-CMC edible film during storage. The method used in this study is a laboratory experimental method which consists of two stages, namely preliminary research which aims to determine the best edible film formula to be used as jelly candy packaging and the main research to analyze changes in the number of molds and the level of acceptance of appearance, taste, aroma and texture of jelly candy that has been packaged using a gelatin-CMC edible film during storage. Storage for 60 days was converted to 15 days in a climatic chamber with a temperature of 40 ℃ and a humidity of 75%. Sampling was carried out every 3 days. The research design used linear regression to see the relationship between storage time and test parameters. The results of the preliminary study showed the best formula for edible film, namely 1% gelatin, 0.3% bees wax, 0.75% CMC, and 0.3% glycerol which resulted in a water vapor transmission rate of 18.60 g/m2/24 hours. The results of the main study showed that storage time had a moderate effect on mold. Mold was detected on the last day of observation, storage time had a very strong effect on the level of acceptance which decreased with storage time. The organoleptic value of jelly candy packaged using gelatin-CMC edible film was still acceptable to the panelists until the 36th day of storage.


2015 ◽  
Vol 22 (1) ◽  
pp. 125-140
Author(s):  
Vinh Nguyen Thi Hong

The paper aims at exploring the relationship between bad debt and cost efficiency in Vietnamese commercial banks in the years 2007 – 2013. The research includes two stages: (i) Measuring the cost efficiency of banks by non-parameter Data Envelopment Analysis (DEA) method suggested by Coelli (2005); and (ii) Applying the Tobit model to identify two-way effects of bad debt and bank cost efficiency. The results show that the cost efficiency in Vietnamese commercial banks is 52.6% and there exists a direct relationship between bad debt and cost efficiency.


2021 ◽  
Vol 72 (1) ◽  
Author(s):  
Said Hafidh ◽  
David Honys

The gametophyte represents the sexual phase in the alternation of generations in plants; the other, nonsexual phase is the sporophyte. Here, we review the evolutionary origins of the male gametophyte among land plants and, in particular, its ontogenesis in flowering plants. The highly reduced male gametophyte of angiosperm plants is a two- or three-celled pollen grain. Its task is the production of two male gametes and their transport to the female gametophyte, the embryo sac, where double fertilization takes place. We describe two phases of pollen ontogenesis—a developmental phase leading to the differentiation of the male germline and the formation of a mature pollen grain and a functional phase representing the pollen tube growth, beginning with the landing of the pollen grain on the stigma and ending with double fertilization. We highlight recent advances in the complex regulatory mechanisms involved, including posttranscriptional regulation and transcript storage, intracellular metabolic signaling, pollen cell wall structure and synthesis, protein secretion, and phased cell–cell communication within the reproductive tissues. Expected final online publication date for the Annual Review of Plant Biology, Volume 72 is May 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


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