The Experts below are selected from a list of 174 Experts worldwide ranked by ideXlab platform
Franco Giorgi - One of the best experts on this subject based on the ideXlab platform.
-
mono and polyclonal antibodies as probes to study vitellin processing in embryos of the stick insect carausius morosus
Comparative Biochemistry and Physiology B, 1998Co-Authors: Massimo Masetti, Antonella Cecchettini, Franco GiorgiAbstract:Abstract During embryonic development, insect vitellins (Vt) are degraded by limited proteolysis to yield a number of lower-molecular weight Polypeptides. The aim of the present study was to identify these Polypeptides in the embryo and to verify how they relate to Vt Polypeptides deposited in the oocyte during vitellogenesis. To this end a panel of poly- and monoclonal antibodies (Pab, Mab) was raised against Vt Polypeptides and employed by immunoelectrophoresis and immunoblotting on embryos belonging to different developmental stages. Through this approach three major staining patterns were observed. First, Mab 4 reacts with both Polypeptides B 1 and E 20 , suggesting that Polypeptide B 1 is gradually trimmed to yield Polypeptide E 20 in late embryos. Second, Mab 12 is specific for Polypeptide A 3 which is retained unchanged throughout embryogenesis. Third, Pab anti-A 2 and Mab 13 show that Polypeptide A 2 is processed to yield Polypeptide E 9 through limited proteolysis. In conclusion, the staining patterns reported in this study show that Vt Polypeptides in developing embryos of the stick insect Carausius morosus undergo at least two major processing events concerning Polypeptides B 1 and A 2 .
-
a fat body derived protein is selectively sulfated during transit to ovarian follicles in the stick insect carausius morosus
Developmental Biology, 1995Co-Authors: Franco Giorgi, Antonella Cecchettini, Massimo Masetti, M. T. Locci, Jt BradleyAbstract:A monoclonal antibody raised against ovarian follicles of the stick insect Carausius morosus reacted with two related Polypeptides of 157 and 85 kDa in both the ovary and the hemolymph. In vitro cultured fat body proved capable of releasing the 157-kDa Polypeptide into the culture medium and processing it to the lower-molecular-weight Polypeptide of 85 kDa. This was further demonstrated by in vitro exposure to [35S]methionine. Under the same culturing conditions, ovarian follicles proved incapable of synthesizing and/or secreting the 85-kDa Polypeptide. However, in vivo [35S]methionine-labeled ovarian follicles released both Polypeptides when cultured in vitro for up to 24 hr. Vitellogenin Polypeptides were labeled in vivo following exposure to [3H]glucosamine, while 157- and 85-kDa Polypeptides were labeled only in ovarian follicles exposed in vivo to sodium [35S]sulfate. Under in vitro conditions, the 157-kDa Polypeptide could be labeled with sodium [35S]sulfate only if ovarian follicles were cocultured with fat body. No sulfation occurred in fat body or ovarian follicles cultured separately. These experiments suggest that the 157-kDa Polypeptide is a fat body-derived Polypeptide that is sulfated upon transfer to the ovarian follicle.
-
postendocytic vitellin processing in ovarian follicles of the stick insect carausius morosus br
Archives of Insect Biochemistry and Physiology, 1993Co-Authors: Franco Giorgi, Vincenzo Ignacchiti, Massimo Masetti, Antonella Cecchettini, James T. BradleyAbstract:Newly laid eggs of the stick insect Carausius morosus contain two native vitellins (Vit A and Vit B). Under denaturing conditions, these vitellins resolved into 3 (A1, A2, and A3) and 2 (B1 and B2) Polypeptides. All of these Polypeptides had counterparts in the female hemolymph from which they were shown to be derived by in vivo labelling. During ovarian development, the 2 vitellins changed both in charge and Polypeptide composition. In EV and LV follicles, Vit A resolved into 4 distinct vitellin Polypeptides (A0, A1, A2 and A3). Using a panel of monoclonal antibodies, Polypeptide A0 proved to be immunologically related to Polypeptide A2. In follicles about to begin choriongenesis, Polypeptide A3 was gradually replaced by a lower Mr Polypeptide. Over the same time period, Polypeptide B1 changed in charge, but not in Mr. To confirm the existence of a Polypeptide processing in C. morosus, ovarian follicles of different developmental stages were exposed in vivo to [35S]-methionine from 6 to 72 h. Data showed that A0 and B1 were the Polypeptides most heavily labelled after short time exposures to the radioisotope. Polypeptides B2 and A3 were also labelled to some extent. With progressively longer exposures, Polypeptides A1 and A2 also became labelled. In vivo exposure to [3H]-GlcNAc caused all vitellin Polypeptides to become heavily labelled. Autoradiographic analysis of ovarian follicles labelled this way showed that, during development, radioactivity was gradually transferred from newly formed yolk spheres in the cortical ooplasm to the central ooplasm. Data were interpreted as suggesting a causal relationship between Polypeptide processing and progressive yolk sphere fusion to yield the central ooplasm. © 1993 Wiley-Liss, Inc.
Massimo Masetti - One of the best experts on this subject based on the ideXlab platform.
-
mono and polyclonal antibodies as probes to study vitellin processing in embryos of the stick insect carausius morosus
Comparative Biochemistry and Physiology B, 1998Co-Authors: Massimo Masetti, Antonella Cecchettini, Franco GiorgiAbstract:Abstract During embryonic development, insect vitellins (Vt) are degraded by limited proteolysis to yield a number of lower-molecular weight Polypeptides. The aim of the present study was to identify these Polypeptides in the embryo and to verify how they relate to Vt Polypeptides deposited in the oocyte during vitellogenesis. To this end a panel of poly- and monoclonal antibodies (Pab, Mab) was raised against Vt Polypeptides and employed by immunoelectrophoresis and immunoblotting on embryos belonging to different developmental stages. Through this approach three major staining patterns were observed. First, Mab 4 reacts with both Polypeptides B 1 and E 20 , suggesting that Polypeptide B 1 is gradually trimmed to yield Polypeptide E 20 in late embryos. Second, Mab 12 is specific for Polypeptide A 3 which is retained unchanged throughout embryogenesis. Third, Pab anti-A 2 and Mab 13 show that Polypeptide A 2 is processed to yield Polypeptide E 9 through limited proteolysis. In conclusion, the staining patterns reported in this study show that Vt Polypeptides in developing embryos of the stick insect Carausius morosus undergo at least two major processing events concerning Polypeptides B 1 and A 2 .
-
a fat body derived protein is selectively sulfated during transit to ovarian follicles in the stick insect carausius morosus
Developmental Biology, 1995Co-Authors: Franco Giorgi, Antonella Cecchettini, Massimo Masetti, M. T. Locci, Jt BradleyAbstract:A monoclonal antibody raised against ovarian follicles of the stick insect Carausius morosus reacted with two related Polypeptides of 157 and 85 kDa in both the ovary and the hemolymph. In vitro cultured fat body proved capable of releasing the 157-kDa Polypeptide into the culture medium and processing it to the lower-molecular-weight Polypeptide of 85 kDa. This was further demonstrated by in vitro exposure to [35S]methionine. Under the same culturing conditions, ovarian follicles proved incapable of synthesizing and/or secreting the 85-kDa Polypeptide. However, in vivo [35S]methionine-labeled ovarian follicles released both Polypeptides when cultured in vitro for up to 24 hr. Vitellogenin Polypeptides were labeled in vivo following exposure to [3H]glucosamine, while 157- and 85-kDa Polypeptides were labeled only in ovarian follicles exposed in vivo to sodium [35S]sulfate. Under in vitro conditions, the 157-kDa Polypeptide could be labeled with sodium [35S]sulfate only if ovarian follicles were cocultured with fat body. No sulfation occurred in fat body or ovarian follicles cultured separately. These experiments suggest that the 157-kDa Polypeptide is a fat body-derived Polypeptide that is sulfated upon transfer to the ovarian follicle.
-
postendocytic vitellin processing in ovarian follicles of the stick insect carausius morosus br
Archives of Insect Biochemistry and Physiology, 1993Co-Authors: Franco Giorgi, Vincenzo Ignacchiti, Massimo Masetti, Antonella Cecchettini, James T. BradleyAbstract:Newly laid eggs of the stick insect Carausius morosus contain two native vitellins (Vit A and Vit B). Under denaturing conditions, these vitellins resolved into 3 (A1, A2, and A3) and 2 (B1 and B2) Polypeptides. All of these Polypeptides had counterparts in the female hemolymph from which they were shown to be derived by in vivo labelling. During ovarian development, the 2 vitellins changed both in charge and Polypeptide composition. In EV and LV follicles, Vit A resolved into 4 distinct vitellin Polypeptides (A0, A1, A2 and A3). Using a panel of monoclonal antibodies, Polypeptide A0 proved to be immunologically related to Polypeptide A2. In follicles about to begin choriongenesis, Polypeptide A3 was gradually replaced by a lower Mr Polypeptide. Over the same time period, Polypeptide B1 changed in charge, but not in Mr. To confirm the existence of a Polypeptide processing in C. morosus, ovarian follicles of different developmental stages were exposed in vivo to [35S]-methionine from 6 to 72 h. Data showed that A0 and B1 were the Polypeptides most heavily labelled after short time exposures to the radioisotope. Polypeptides B2 and A3 were also labelled to some extent. With progressively longer exposures, Polypeptides A1 and A2 also became labelled. In vivo exposure to [3H]-GlcNAc caused all vitellin Polypeptides to become heavily labelled. Autoradiographic analysis of ovarian follicles labelled this way showed that, during development, radioactivity was gradually transferred from newly formed yolk spheres in the cortical ooplasm to the central ooplasm. Data were interpreted as suggesting a causal relationship between Polypeptide processing and progressive yolk sphere fusion to yield the central ooplasm. © 1993 Wiley-Liss, Inc.
Antonella Cecchettini - One of the best experts on this subject based on the ideXlab platform.
-
mono and polyclonal antibodies as probes to study vitellin processing in embryos of the stick insect carausius morosus
Comparative Biochemistry and Physiology B, 1998Co-Authors: Massimo Masetti, Antonella Cecchettini, Franco GiorgiAbstract:Abstract During embryonic development, insect vitellins (Vt) are degraded by limited proteolysis to yield a number of lower-molecular weight Polypeptides. The aim of the present study was to identify these Polypeptides in the embryo and to verify how they relate to Vt Polypeptides deposited in the oocyte during vitellogenesis. To this end a panel of poly- and monoclonal antibodies (Pab, Mab) was raised against Vt Polypeptides and employed by immunoelectrophoresis and immunoblotting on embryos belonging to different developmental stages. Through this approach three major staining patterns were observed. First, Mab 4 reacts with both Polypeptides B 1 and E 20 , suggesting that Polypeptide B 1 is gradually trimmed to yield Polypeptide E 20 in late embryos. Second, Mab 12 is specific for Polypeptide A 3 which is retained unchanged throughout embryogenesis. Third, Pab anti-A 2 and Mab 13 show that Polypeptide A 2 is processed to yield Polypeptide E 9 through limited proteolysis. In conclusion, the staining patterns reported in this study show that Vt Polypeptides in developing embryos of the stick insect Carausius morosus undergo at least two major processing events concerning Polypeptides B 1 and A 2 .
-
a fat body derived protein is selectively sulfated during transit to ovarian follicles in the stick insect carausius morosus
Developmental Biology, 1995Co-Authors: Franco Giorgi, Antonella Cecchettini, Massimo Masetti, M. T. Locci, Jt BradleyAbstract:A monoclonal antibody raised against ovarian follicles of the stick insect Carausius morosus reacted with two related Polypeptides of 157 and 85 kDa in both the ovary and the hemolymph. In vitro cultured fat body proved capable of releasing the 157-kDa Polypeptide into the culture medium and processing it to the lower-molecular-weight Polypeptide of 85 kDa. This was further demonstrated by in vitro exposure to [35S]methionine. Under the same culturing conditions, ovarian follicles proved incapable of synthesizing and/or secreting the 85-kDa Polypeptide. However, in vivo [35S]methionine-labeled ovarian follicles released both Polypeptides when cultured in vitro for up to 24 hr. Vitellogenin Polypeptides were labeled in vivo following exposure to [3H]glucosamine, while 157- and 85-kDa Polypeptides were labeled only in ovarian follicles exposed in vivo to sodium [35S]sulfate. Under in vitro conditions, the 157-kDa Polypeptide could be labeled with sodium [35S]sulfate only if ovarian follicles were cocultured with fat body. No sulfation occurred in fat body or ovarian follicles cultured separately. These experiments suggest that the 157-kDa Polypeptide is a fat body-derived Polypeptide that is sulfated upon transfer to the ovarian follicle.
-
postendocytic vitellin processing in ovarian follicles of the stick insect carausius morosus br
Archives of Insect Biochemistry and Physiology, 1993Co-Authors: Franco Giorgi, Vincenzo Ignacchiti, Massimo Masetti, Antonella Cecchettini, James T. BradleyAbstract:Newly laid eggs of the stick insect Carausius morosus contain two native vitellins (Vit A and Vit B). Under denaturing conditions, these vitellins resolved into 3 (A1, A2, and A3) and 2 (B1 and B2) Polypeptides. All of these Polypeptides had counterparts in the female hemolymph from which they were shown to be derived by in vivo labelling. During ovarian development, the 2 vitellins changed both in charge and Polypeptide composition. In EV and LV follicles, Vit A resolved into 4 distinct vitellin Polypeptides (A0, A1, A2 and A3). Using a panel of monoclonal antibodies, Polypeptide A0 proved to be immunologically related to Polypeptide A2. In follicles about to begin choriongenesis, Polypeptide A3 was gradually replaced by a lower Mr Polypeptide. Over the same time period, Polypeptide B1 changed in charge, but not in Mr. To confirm the existence of a Polypeptide processing in C. morosus, ovarian follicles of different developmental stages were exposed in vivo to [35S]-methionine from 6 to 72 h. Data showed that A0 and B1 were the Polypeptides most heavily labelled after short time exposures to the radioisotope. Polypeptides B2 and A3 were also labelled to some extent. With progressively longer exposures, Polypeptides A1 and A2 also became labelled. In vivo exposure to [3H]-GlcNAc caused all vitellin Polypeptides to become heavily labelled. Autoradiographic analysis of ovarian follicles labelled this way showed that, during development, radioactivity was gradually transferred from newly formed yolk spheres in the cortical ooplasm to the central ooplasm. Data were interpreted as suggesting a causal relationship between Polypeptide processing and progressive yolk sphere fusion to yield the central ooplasm. © 1993 Wiley-Liss, Inc.
Jt Bradley - One of the best experts on this subject based on the ideXlab platform.
-
a fat body derived protein is selectively sulfated during transit to ovarian follicles in the stick insect carausius morosus
Developmental Biology, 1995Co-Authors: Franco Giorgi, Antonella Cecchettini, Massimo Masetti, M. T. Locci, Jt BradleyAbstract:A monoclonal antibody raised against ovarian follicles of the stick insect Carausius morosus reacted with two related Polypeptides of 157 and 85 kDa in both the ovary and the hemolymph. In vitro cultured fat body proved capable of releasing the 157-kDa Polypeptide into the culture medium and processing it to the lower-molecular-weight Polypeptide of 85 kDa. This was further demonstrated by in vitro exposure to [35S]methionine. Under the same culturing conditions, ovarian follicles proved incapable of synthesizing and/or secreting the 85-kDa Polypeptide. However, in vivo [35S]methionine-labeled ovarian follicles released both Polypeptides when cultured in vitro for up to 24 hr. Vitellogenin Polypeptides were labeled in vivo following exposure to [3H]glucosamine, while 157- and 85-kDa Polypeptides were labeled only in ovarian follicles exposed in vivo to sodium [35S]sulfate. Under in vitro conditions, the 157-kDa Polypeptide could be labeled with sodium [35S]sulfate only if ovarian follicles were cocultured with fat body. No sulfation occurred in fat body or ovarian follicles cultured separately. These experiments suggest that the 157-kDa Polypeptide is a fat body-derived Polypeptide that is sulfated upon transfer to the ovarian follicle.
Xuesi Chen - One of the best experts on this subject based on the ideXlab platform.
-
stimuli sensitive synthetic Polypeptide based materials for drug and gene delivery
Advanced Healthcare Materials, 2012Co-Authors: Xiuli Zhuang, Zhaohui Tang, Huayu Tian, Xuesi ChenAbstract:Stimuli-sensitive synthetic Polypeptides are unique biodegradable and biocompatible synthetic polymers with structures mimicking natural proteins. These polymers exhibit reversible secondary conformation transitions and/or hydrophilic-hydrophobic transitions in response to changes in environmental conditions such as pH and temperature. The stimuli-triggered conformation and/or phase transitions lead to unique self-assembly behaviors, making these materials interesting for controlled drug and gene delivery applications. Therefore, stimuli-sensitive synthetic Polypeptide-based materials have been extensively investigatid in recent years. Various Polypeptide-based materials, including micelles, vesicles, nanogels, and hydrogels, have been developed and tested for drug- and gene-delivery applications. In addition, the presence of reactive side groups in some Polypeptides facilitates the incorporation of various functional moieties to the Polypeptides. This Review focuses on recent advances in stimuli-sensitive Polypeptide-based materials that have been designed and evaluated for drug and gene delivery applications. In addition, recent developments in the preparation of stimuli-sensitive functionalized Polypeptides are discussed.
