Microscopic characterization of a transposon-induced male-sterile, female-sterile mutant in Glycine max L.

A male-sterile, female-sterile mutant was identified in a transposon-tagging study in soybean (Glycine max L.). This mutant displayed abnormalities in both micro- and mega-sporogenesis, as well as gametogenesis. Vegetatively, the mutant showed no visible differences from the wild-type phenotype. Analyses of male meiotic chromosomes were done to better understand any issues that could occur to cause sterility. Wild-type and mutant anthers and ovules were cleared throughout their development, followed by confocal scanning laser microscopy to look for any abnormalities, and to determine the timing of abortion in both the male and female organs in the mutant. Additionally, scanning electron microscopy was done to observe the differences between wild-type and mutant anthers and male cells near maturity and mutant abortion. Results indicate there are chromosomal segregation abnormalities in the mutant male meiosis. Mutant anther development proceeds through meiosis to form abnormal triads, tetrads and pentads to the released microspore stage, after which the resulting male cells become irregularly shaped and eventually abort. Mutant megasporogenesis proceeds through meiosis from megaspore mother cell through two meiotic divisions resulting in the tetrad stage which then progresses to the single megaspore and to the early formation of a megagametophyte which ceases further development These first-time cytological and anatomical results were compared with an already-published molecular study of this sterile soy mutant and to provide insights into this dual sterility in soybean

Microscopic Characterization of a Transposon-Induced Male-Sterile, Female-Sterile Mutant in Glycine max L.

Premise of research. A male-sterile, female-sterile mutant was discovered in a w4-m mutable line of Glycine max L. The mechanism of its sterility was not well understood. Therefore, different cytological and microscopic techniques were undertaken to better understand the process of mutant phenotype development. Molecular research indicated that mer3 was responsible for the sterility. Methodology. Macro images were collected of whole plants, flowers, anthers, pods, and ovules. Chromosome spreads from anthers at various meiotic stages were examined. Confocal scanning laser microscopy using optical sectioning was utilized on whole anthers and ovules at various developmental stages. Whole mature anthers and isolated pollen images were collected and studied with SEM. Pivotal results. In observations of the mutant, male cell development was found to begin normally and then digresses at metaphase I of meiosis, when abnormal segregation of chromosomes with reduced bivalent formation was observed. It was the abnormal formation of univalents and bivalents that led to male sterility. On the female side, the progression of development was arrested in the megagametophyte stage likely because of abnormal meiosis, leading to ovule abortion and female sterility. Conclusions. The G. max male-sterile, female-sterile mutant was shown to have the same phenotype of mer3 sterility already shown in Arabidopsis, rice, yeast, and some animal systems

Microscopic characterization of a transposon-induced male-sterile, female-sterile mutant in Glycine max L.

A male-sterile, female-sterile mutant was identified in a transposon-tagging study in soybean (Glycine max L.). This mutant displayed abnormalities in both micro- and mega-sporogenesis, as well as gametogenesis. Vegetatively, the mutant showed no visible differences from the wild-type phenotype. Analyses of male meiotic chromosomes were done to better understand any issues that could occur to cause sterility. Wild-type and mutant anthers and ovules were cleared throughout their development, followed by confocal scanning laser microscopy to look for any abnormalities, and to determine the timing of abortion in both the male and female organs in the mutant. Additionally, scanning electron microscopy was done to observe the differences between wild-type and mutant anthers and male cells near maturity and mutant abortion. Results indicate there are chromosomal segregation abnormalities in the mutant male meiosis. Mutant anther development proceeds through meiosis to form abnormal triads, tetrads and pentads to the released microspore stage, after which the resulting male cells become irregularly shaped and eventually abort. Mutant megasporogenesis proceeds through meiosis from megaspore mother cell through two meiotic divisions resulting in the tetrad stage which then progresses to the single megaspore and to the early formation of a megagametophyte which ceases further development These first-time cytological and anatomical results were compared with an already-published molecular study of this sterile soy mutant and to provide insights into this dual sterility in soybean.</p

Microscopic characterization of a transposon-induced male-sterile, female-sterile mutant in Glycine max L.

A male-sterile, female-sterile mutant was identified in a transposon-tagging study in soybean (Glycine max L.). This mutant displayed abnormalities in both micro- and mega-sporogenesis, as well as gametogenesis. Vegetatively, the mutant showed no visible differences from the wild-type phenotype. Analyses of male meiotic chromosomes were done to better understand any issues that could occur to cause sterility. Wild-type and mutant anthers and ovules were cleared throughout their development, followed by confocal scanning laser microscopy to look for any abnormalities, and to determine the timing of abortion in both the male and female organs in the mutant. Additionally, scanning electron microscopy was done to observe the differences between wild-type and mutant anthers and male cells near maturity and mutant abortion. Results indicate there are chromosomal segregation abnormalities in the mutant male meiosis. Mutant anther development proceeds through meiosis to form abnormal triads, tetrads and pentads to the released microspore stage, after which the resulting male cells become irregularly shaped and eventually abort. Mutant megasporogenesis proceeds through meiosis from megaspore mother cell through two meiotic divisions resulting in the tetrad stage which then progresses to the single megaspore and to the early formation of a megagametophyte which ceases further development These first-time cytological and anatomical results were compared with an already-published molecular study of this sterile soy mutant and to provide insights into this dual sterility in soybean.</p

Microscopic Characterization of a Transposon-Induced Male-Sterile, Female-Sterile Mutant in Glycine max L.

Premise of research. A male-sterile, female-sterile mutant was discovered in a w4-m mutable line of Glycine max L. The mechanism of its sterility was not well understood. Therefore, different cytological and microscopic techniques were undertaken to better understand the process of mutant phenotype development. Molecular research indicated that mer3 was responsible for the sterility. Methodology. Macro images were collected of whole plants, flowers, anthers, pods, and ovules. Chromosome spreads from anthers at various meiotic stages were examined. Confocal scanning laser microscopy using optical sectioning was utilized on whole anthers and ovules at various developmental stages. Whole mature anthers and isolated pollen images were collected and studied with SEM. Pivotal results. In observations of the mutant, male cell development was found to begin normally and then digresses at metaphase I of meiosis, when abnormal segregation of chromosomes with reduced bivalent formation was observed. It was the abnormal formation of univalents and bivalents that led to male sterility. On the female side, the progression of development was arrested in the megagametophyte stage likely because of abnormal meiosis, leading to ovule abortion and female sterility. Conclusions. The G. max male-sterile, female-sterile mutant was shown to have the same phenotype of mer3 sterility already shown in Arabidopsis, rice, yeast, and some animal systems.This article is published as Thilges, Katherine A., Mark A. Chamberlin, Marc C. Albertsen, and Harry T. Horner. "Microscopic characterization of a transposon-induced male-sterile, female-sterile mutant in Glycine max L." International Journal of Plant Sciences 178, no. 8 (2017): 629-638. doi: 10.1086/693857. Posted with permission.</p

Improving Health Care Information Systems for a Community Health Network (semester?), IPRO 340: IS Systems for Comm Health Service Network IPRO 340 Abstract F06

Assess the referral process and assess the perceptions and feelings of employees involved in the referral process. Determine if any changes need to be made to the referral process and see what can be done to make the referral process easier and less stressful for the employees involved.Sponsorship: Steven Glass, CIO Access Health NetworkDeliverables for IPRO 340: Improving Health Care Information Systems for a Community Health Network for the Fall 2006 semeste

Improving Health Care Information Systems for a Community Health Network (semester?), IPRO 340

Assess the referral process and assess the perceptions and feelings of employees involved in the referral process. Determine if any changes need to be made to the referral process and see what can be done to make the referral process easier and less stressful for the employees involved.Sponsorship: Steven Glass, CIO Access Health NetworkDeliverables for IPRO 340: Improving Health Care Information Systems for a Community Health Network for the Fall 2006 semeste

Improving Health Care Information Systems for a Community Health Network (semester?), IPRO 340: IS Systems for Comm Health Service Network IPRO 340 Final Report F06

Assess the referral process and assess the perceptions and feelings of employees involved in the referral process. Determine if any changes need to be made to the referral process and see what can be done to make the referral process easier and less stressful for the employees involved.Sponsorship: Steven Glass, CIO Access Health NetworkDeliverables for IPRO 340: Improving Health Care Information Systems for a Community Health Network for the Fall 2006 semeste

Improving Health Care Information Systems for a Community Health Network (semester?), IPRO 340: IS Systems for Comm Health Service Network IPRO 340 Poster F06

Assess the referral process and assess the perceptions and feelings of employees involved in the referral process. Determine if any changes need to be made to the referral process and see what can be done to make the referral process easier and less stressful for the employees involved.Sponsorship: Steven Glass, CIO Access Health NetworkDeliverables for IPRO 340: Improving Health Care Information Systems for a Community Health Network for the Fall 2006 semeste

Improving Health Care Information Systems for a Community Health Network (semester?), IPRO 340: IS Systems for Comm Health Service Network IPRO 340 Project Plan F06

Assess the referral process and assess the perceptions and feelings of employees involved in the referral process. Determine if any changes need to be made to the referral process and see what can be done to make the referral process easier and less stressful for the employees involved.Sponsorship: Steven Glass, CIO Access Health NetworkDeliverables for IPRO 340: Improving Health Care Information Systems for a Community Health Network for the Fall 2006 semeste