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Article: Global Deletion of ALDH1A1 and ALDH1A2 Genes Does Not Affect Viability but Blocks Spermatogenesis.

Topping, Traci / Griswold, Michael D

2022 Volume 13, Page(s) 871225

Abstract: The transition of undifferentiated A spermatogonia to differentiated spermatogonia requires the action of retinoic acid (RA). The synthesis of retinoic acid from retinal in the seminiferous epithelium is a result of the action of aldehyde dehydrogenases ... ...

Abstract	The transition of undifferentiated A spermatogonia to differentiated spermatogonia requires the action of retinoic acid (RA). The synthesis of retinoic acid from retinal in the seminiferous epithelium is a result of the action of aldehyde dehydrogenases termed ALDH1A1, ALDH1A2, and ALDH1A3. We used a mouse with a global deletion of the
MeSH term(s)	Aldehyde Dehydrogenase 1 Family/metabolism ; Animals ; Cell Differentiation ; Male ; Mice ; Retinal Dehydrogenase/genetics ; Retinal Dehydrogenase/metabolism ; Sertoli Cells ; Spermatogenesis/genetics ; Spermatogonia ; Tretinoin
Chemical Substances	Tretinoin (5688UTC01R) ; Aldehyde Dehydrogenase 1 Family (EC 1.2.1) ; ALDH1A1 protein, mouse (EC 1.2.1.36) ; Aldh1a2 protein, mouse (EC 1.2.1.36) ; Retinal Dehydrogenase (EC 1.2.1.36)
Language	English
Publishing date	2022-04-28
Publishing country	Switzerland
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	2592084-4
ISSN	1664-2392
ISSN	1664-2392
DOI	10.3389/fendo.2022.871225
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Article ; Online: Cycles, waves, and pulses: Retinoic acid and the organization of spermatogenesis.

Gewiss, Rachel / Topping, Traci / Griswold, Michael D

Andrology

2019 Volume 8, Issue 4, Page(s) 892–897

Abstract: Background: Spermatogenesis in mammals is organized in a manner that maximizes sperm production. The central aspect of this organization is the cycle of the seminiferous epithelium that is characterized by an asynchronous repeating series of germ cell ... ...

Abstract	Background: Spermatogenesis in mammals is organized in a manner that maximizes sperm production. The central aspect of this organization is the cycle of the seminiferous epithelium that is characterized by an asynchronous repeating series of germ cell associations. These cell associations are the result of a fixed point of entry into the cycle at regular short time intervals and the longer time required for cells to fully differentiate and exit the cycle. Objective: This review will examine the current information on the action and metabolism of retinoic acid in the testis, the interaction of retinoic acid (RA) with the cycle and the spermatogenic wave, and the mechanisms that can lead to synchronous spermatogenesis. Finally, the unique applications of synchronous spermatogenesis to the study of the cycle and the mass isolation of specific germ cell populations are described. Materials and methods: Retinoic acid metabolism and spermatogonial differentiation have been examined by gene deletions, immunocytochemistry, chemical inhibitors, and mass spectrometry. Results, discussion, and conclusion: Both the Sertoli cells and the germ cells have the capacity to synthesize retinoic acid from retinol and in the mouse the entry into the cycle of the seminiferous epithelium, and the subsequent conversion of undifferentiated spermatogonia into differentiating spermatogonia is governed by a peak of RA synthesis occurring at stages VIII-IX of the cycle. Normal asynchronous spermatogenesis can be modified by altering RA levels, and as a result the entire testis will consist of a few closely related stages of the cycle.
MeSH term(s)	Animals ; Cell Differentiation ; Humans ; Male ; Mice ; Sertoli Cells/metabolism ; Spermatogenesis/physiology ; Spermatogonia/cytology ; Spermatogonia/metabolism ; Spermatozoa/cytology ; Spermatozoa/metabolism
Language	English
Publishing date	2019-11-20
Publishing country	England
Document type	Journal Article ; Research Support, N.I.H., Extramural ; Review
ZDB-ID	2696108-8
ISSN	2047-2927 ; 2047-2919
ISSN (online)	2047-2927
ISSN	2047-2919
DOI	10.1111/andr.12722
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Article ; Online: Differential localization of histone variant TH2B during the first round compared with subsequent rounds of spermatogenesis.

Beedle, My-Thanh / Topping, Traci / Hogarth, Cathryn / Griswold, Michael

Developmental dynamics : an official publication of the American Association of Anatomists

2019 Volume 248, Issue 6, Page(s) 488–500

Abstract: Background: Male germ cells are unique because they express a substantial number of variants of the general DNA binding proteins, known as histones, yet the biological significance of these variants is still unknown. In the present study, we aimed to ... ...

Abstract	Background: Male germ cells are unique because they express a substantial number of variants of the general DNA binding proteins, known as histones, yet the biological significance of these variants is still unknown. In the present study, we aimed to address the expression pattern of the testis-specific histone H2B variant (TH2B) and the testis-specific histone H2A variant (TH2A) within the neonatal mouse testis. Results: We demonstrate that TH2B and TH2A are present in a testis-enriched for undifferentiated spermatogonia. Co-localization studies with an undifferentiated marker, ZBTB16, revealed that TH2B and ZBTB16 co-localize in the neonatal testis. Upon the appearance of the primary spermatocytes, TH2B no longer co-localized with the ZBTB16 positive spermatogonia but were instead detected within the differentiating spermatogonia. This pattern of expression where TH2B and ZBTB16 no longer co-localize was maintained in the adult testis. Conclusion: These findings are in contrast to previous studies, which demonstrated that TH2B and TH2A were found only in adult spermatocytes. Our data are in support of a switch in the expression of these variants following the first round of spermatogonial differentiation. These studies reinforce current understandings that spermatogonia within the neonatal mouse testis are inherently different from those residing within the adult testis.
MeSH term(s)	Animals ; Animals, Newborn ; Genetic Variation ; Histones/analysis ; Histones/genetics ; Male ; Mice ; Spermatocytes/chemistry ; Spermatogenesis ; Testis/chemistry
Chemical Substances	Histones ; histone H2B type 1-A
Language	English
Publishing date	2019-04-19
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	1102541-4
ISSN	1097-0177 ; 1058-8388
ISSN (online)	1097-0177
ISSN	1058-8388
DOI	10.1002/dvdy.33
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Article ; Online: The impact of solubility and electrostatics on fibril formation by the H3 and H4 histones.

Topping, Traci B / Gloss, Lisa M

Protein science : a publication of the Protein Society

2011 Volume 20, Issue 12, Page(s) 2060–2073

Abstract: The goal of this study was to examine fibril formation by the heterodimeric eukaryotic histones (H2A-H2B and H3-H4) and homodimeric archaeal histones (hMfB and hPyA1). The histone fold dimerization motif is an obligatorily domain-swapped structure ... ...

Abstract	The goal of this study was to examine fibril formation by the heterodimeric eukaryotic histones (H2A-H2B and H3-H4) and homodimeric archaeal histones (hMfB and hPyA1). The histone fold dimerization motif is an obligatorily domain-swapped structure comprised of two fused helix:β-loop:helix motifs. Domain swapping has been proposed as a mechanism for the evolution of protein oligomers as well as a means to form precursors in the formation of amyloid-like fibrils. Despite sharing a common fold, the eukaryotic histones of the core nucleosome and archaeal histones fold by kinetic mechanisms of differing complexity with transient population of partially folded monomeric and/or dimeric species. No relationship was apparent between fibrillation propensity and equilibrium stability or population of kinetic intermediates. Only H3 and H4, as isolated monomers and as a heterodimer, readily formed fibrils at room temperature, and this propensity correlates with the significantly lower solubility of these polypeptides. The fibrils were characterized by ThT fluorescence, FTIR, and far-UV CD spectroscopies and electron microscopy. The helical histone fold comprises the protease-resistant core of the fibrils, with little or no protease protection of the poorly structured N-terminal tails. The highly charged tails inhibit fibrillation through electrostatic repulsion. Kinetic studies indicate that H3 and H4 form a co-fibril, with simultaneous incorporation of both histones. The potential impact of H3 and H4 fibrillation on the cytotoxicity of extracellular histones and α-synuclein-mediated neurotoxicity and fibrillation is considered.
MeSH term(s)	Amyloid/chemistry ; Amyloid/metabolism ; Animals ; Archaeal Proteins/chemistry ; Archaeal Proteins/metabolism ; Histones/chemistry ; Histones/metabolism ; Models, Molecular ; Protein Folding ; Protein Multimerization ; Protein Structure, Secondary ; Protein Structure, Tertiary ; Solubility ; Static Electricity ; Xenopus laevis
Chemical Substances	Amyloid ; Archaeal Proteins ; Histones
Language	English
Publishing date	2011-11-09
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	1106283-6
ISSN	1469-896X ; 0961-8368
ISSN (online)	1469-896X
ISSN	0961-8368
DOI	10.1002/pro.743
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Zs.A 3407: Show issues			Location: Je nach Verfügbarkeit (siehe Angabe bei Bestand) bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular Jg. 1995 - 2021: Lesesall (2.OG) ab Jg. 2022: Lesesaal (EG)
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Article ; Online: Retinoic acid receptor signaling is necessary in steroidogenic cells for normal spermatogenesis and epididymal function.

Jauregui, Estela J / Mitchell, Debra / Topping, Traci / Hogarth, Cathryn A / Griswold, Michael D

Development (Cambridge, England)

2018 Volume 145, Issue 13

Abstract: Spermatogenesis in mammals is a very complex, highly organized process, regulated in part by testosterone and retinoic acid (RA). Much is known about how RA and testosterone signaling pathways independently regulate this process, but there is almost no ... ...

Abstract	Spermatogenesis in mammals is a very complex, highly organized process, regulated in part by testosterone and retinoic acid (RA). Much is known about how RA and testosterone signaling pathways independently regulate this process, but there is almost no information regarding whether these two signaling pathways directly interact and whether RA is crucial for steroidogenic cell function. This study uses a transgenic mouse line that expresses a dominant-negative form of RA receptor α (RAR-DN) and the steroidogenic cell-specific Cre mouse line,
MeSH term(s)	Animals ; Blood-Testis Barrier/cytology ; Blood-Testis Barrier/metabolism ; Fertility/physiology ; Male ; Mice ; Mice, Transgenic ; Retinoic Acid Receptor alpha/genetics ; Retinoic Acid Receptor alpha/metabolism ; Signal Transduction/physiology ; Spermatocytes/cytology ; Spermatocytes/metabolism ; Spermatogenesis/physiology ; Steroid 17-alpha-Hydroxylase/genetics ; Steroid 17-alpha-Hydroxylase/metabolism
Chemical Substances	Rara protein, mouse ; Retinoic Acid Receptor alpha ; Steroid 17-alpha-Hydroxylase (EC 1.14.14.19)
Language	English
Publishing date	2018-07-09
Publishing country	England
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	90607-4
ISSN	1477-9129 ; 0950-1991
ISSN (online)	1477-9129
ISSN	0950-1991
DOI	10.1242/dev.160465
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Article ; Online: Leydig cell genes change their expression and association with polysomes in a stage-specific manner in the adult mouse testis.

Jauregui, Estela J / Mitchell, Debra / Garza, Savanna M / Topping, Traci / Hogarth, Cathryn A / Griswold, Michael D

Biology of reproduction

2018 Volume 98, Issue 5, Page(s) 722–738

Abstract: Spermatogenesis in mammals occurs in a very highly organized manner within the seminiferous epithelium regulated by different cell types in the testis. Testosterone produced by Leydig cells regulates blood-testis barrier formation, meiosis, ... ...

Abstract	Spermatogenesis in mammals occurs in a very highly organized manner within the seminiferous epithelium regulated by different cell types in the testis. Testosterone produced by Leydig cells regulates blood-testis barrier formation, meiosis, spermiogenesis, and spermiation. However, it is unknown whether Leydig cell function changes with the different stages of the seminiferous epithelium. This study utilized the WIN 18,446 and retinoic acid (RA) treatment regime combined with the RiboTag mouse methodology to synchronize male germ cell development and allow for the in vivo mapping of the Leydig cell translatome across the different stages of one cycle of the seminiferous epithelium. Using microarrays analysis, we identified 11 Leydig cell-enriched genes that were expressed in stage-specific manner such as the glucocorticoid synthesis and transport genes, Cyp21a1 and Serpina6. In addition, there were nine Leydig cell transcripts that change their association with polysomes in correlation with the different stages of the spermatogenic cycle including Egr1. Interestingly, the signal intensity of EGR1 and CYP21 varied among Leydig cells in the adult asynchronous testis. However, testosterone levels across the different stages of germ cell development did not cycle. These data show, for the first time, that Leydig cell gene expression changes in a stage-specific manner during the cycle of the seminiferous epithelium and indicate that a heterogeneous Leydig cell population exists in the adult mouse testis.
MeSH term(s)	Animals ; Blood-Testis Barrier ; Gene Expression ; Leydig Cells/cytology ; Leydig Cells/metabolism ; Male ; Mice ; Polyribosomes/metabolism ; Seminiferous Epithelium/cytology ; Seminiferous Epithelium/metabolism ; Spermatogenesis/physiology ; Steroid 21-Hydroxylase/genetics ; Steroid 21-Hydroxylase/metabolism ; Testis/cytology ; Testis/metabolism ; Transcortin/genetics ; Transcortin/metabolism
Chemical Substances	Serpina6 protein, mouse ; Transcortin (9010-38-2) ; Cyp21a1 protein, mouse (EC 1.14.14.16) ; Steroid 21-Hydroxylase (EC 1.14.14.16)
Language	English
Publishing date	2018-02-05
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	1118-6
ISSN	1529-7268 ; 0006-3363
ISSN (online)	1529-7268
ISSN	0006-3363
DOI	10.1093/biolre/ioy031
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Zs.A 551: Show issues

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Article ; Online: Sources of all-trans retinal oxidation independent of the aldehyde dehydrogenase 1A isozymes exist in the postnatal testis†.

Beedle, My-Thanh / Stevison, Faith / Zhong, Guo / Topping, Traci / Hogarth, Cathryn / Isoherranen, Nina / Griswold, Michael D

Biology of reproduction

2018 Volume 100, Issue 2, Page(s) 547–560

Abstract: Despite the essential role of the active metabolite of vitamin A, all-trans retinoic acid (atRA) in spermatogenesis, the enzymes, and cellular populations responsible for its synthesis in the postnatal testis remain largely unknown. The aldehyde ... ...

Abstract	Despite the essential role of the active metabolite of vitamin A, all-trans retinoic acid (atRA) in spermatogenesis, the enzymes, and cellular populations responsible for its synthesis in the postnatal testis remain largely unknown. The aldehyde dehydrogenase 1A (ALDH1A) family of enzymes residing within Sertoli cells is responsible for the synthesis of atRA, driving the first round of spermatogenesis. Those studies also revealed that the atRA required to drive subsequent rounds of spermatogenesis is possibly derived from the ALDH1A enzymes residing within the meiotic and post-meiotic germ cells. Three ALDH1A isozymes (ALDH1A1, ALDH1A2, and ALDH1A3) are present in the testis. Although, ALDH1A1 is expressed in adult Sertoli cells and is suggested to contribute to the atRA required for the pre-meiotic transitions, ALDH1A2 is proposed to be the essential isomer involved in testicular atRA biosynthesis. In this report, we first examine the requirement for ALDH1A2 via the generation and analysis of a conditional Aldh1a2 germ cell knockout and a tamoxifen-induced Aldh1a2 knockout model. We then utilized the pan-ALDH1A inhibitor (WIN 18446) to test the collective contribution of the ALDH1A enzymes to atRA biosynthesis following the first round of spermatogenesis. Collectively, our data provide the first in vivo evidence demonstrating that animals severely deficient in ALDH1A2 postnatally proceed normally through spermatogenesis. Our studies with a pan-ALDH1A inhibitor (WIN 18446) also suggest that an alternative source of atRA biosynthesis independent of the ALDH1A enzymes becomes available to maintain atRA levels for several spermatogenic cycles following an initial atRA injection.
MeSH term(s)	Aldehyde Dehydrogenase 1/genetics ; Aldehyde Dehydrogenase 1/metabolism ; Animals ; Gene Expression Regulation, Enzymologic/drug effects ; Genotype ; Isoenzymes ; Male ; Mice ; Mice, Knockout ; Mice, Transgenic ; Oxidation-Reduction ; Spermatogonia/drug effects ; Spermatogonia/metabolism ; Tamoxifen/pharmacology ; Testis/metabolism ; Tretinoin/metabolism
Chemical Substances	Aldehyde Dehydrogenase 1 ; Isoenzymes ; Tamoxifen (094ZI81Y45) ; Tretinoin (5688UTC01R)
Language	English
Publishing date	2018-11-02
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	1118-6
ISSN	1529-7268 ; 0006-3363
ISSN (online)	1529-7268
ISSN	0006-3363
DOI	10.1093/biolre/ioy200
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Article ; Online: Knockout of Cyp26a1 and Cyp26b1 during postnatal life causes reduced lifespan, dermatitis, splenomegaly, and systemic inflammation in mice.

Snyder, Jessica M / Zhong, Guo / Hogarth, Cathryn / Huang, Weize / Topping, Traci / LaFrance, Jeffrey / Palau, Laura / Czuba, Lindsay C / Griswold, Michael / Ghiaur, Gabriel / Isoherranen, Nina

FASEB journal : official publication of the Federation of American Societies for Experimental Biology

2020 Volume 34, Issue 12, Page(s) 15788–15804

Abstract: All-trans-retinoic acid (atRA), the active metabolite of vitamin A, is an essential signaling molecule in all chordates. Global knockouts of the atRA clearing enzymes Cyp26a1 or Cyp26b1 are embryonic lethal. In adult rodents, inhibition of Cyp26a1 and ... ...

Abstract	All-trans-retinoic acid (atRA), the active metabolite of vitamin A, is an essential signaling molecule in all chordates. Global knockouts of the atRA clearing enzymes Cyp26a1 or Cyp26b1 are embryonic lethal. In adult rodents, inhibition of Cyp26a1 and Cyp26b1 increases atRA concentrations and signaling. However, postnatal knockout of Cyp26a1 does not cause a severe phenotype. We hypothesized that Cyp26b1 is the main atRA clearing Cyp in postnatal mammals. This hypothesis was tested by generating tamoxifen-inducible knockout mouse models of Cyp26b1 alone or with Cyp26a1. Both mouse models showed dermatitis, blepharitis, and splenomegaly. Histology showed infiltration of inflammatory cells including neutrophils and T lymphocytes into the skin and hyperkeratosis/hyperplasia of the nonglandular stomach. The mice lacking both Cyp26a1 and Cyp26b1 also had a reduced lifespan, failed to gain weight, and showed fat atrophy. There were significant changes in vitamin A homeostasis. Postnatal knockout of Cyp26b1 resulted in increased atRA concentrations in the skin while the postnatal knockout of both Cyp26a1 and Cyp26b1 resulted in increased atRA concentrations in the liver, serum, skin, spleen, and intestines. This study demonstrates the paramount role of Cyp26b1 in regulating retinoid homeostasis in postnatal life.
MeSH term(s)	Animals ; Dermatitis/metabolism ; Female ; Homeostasis/physiology ; Inflammation/metabolism ; Longevity/physiology ; Mice ; Mice, Knockout ; Neutrophils/metabolism ; Retinoic Acid 4-Hydroxylase/metabolism ; Retinoids/metabolism ; Signal Transduction/physiology ; Splenomegaly/metabolism ; T-Lymphocytes/metabolism ; Vitamin A/metabolism
Chemical Substances	Retinoids ; Vitamin A (11103-57-4) ; Cyp26a1 protein, mouse (EC 1.14.14.1) ; Cyp26b1 protein, mouse (EC 1.14.14.1) ; Retinoic Acid 4-Hydroxylase (EC 1.14.14.1)
Language	English
Publishing date	2020-10-26
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	639186-2
ISSN	1530-6860 ; 0892-6638
ISSN (online)	1530-6860
ISSN	0892-6638
DOI	10.1096/fj.202001734R
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Zs.A 2266: Show issues			Location: Je nach Verfügbarkeit (siehe Angabe bei Bestand) bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular Jg. 1995 - 2021: Lesesall (1.OG) ab Jg. 2022: Lesesaal (EG)
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Article ; Online: Asymmetric unwrapping of nucleosomal DNA propagates asymmetric opening and dissociation of the histone core.

Chen, Yujie / Tokuda, Joshua M / Topping, Traci / Meisburger, Steve P / Pabit, Suzette A / Gloss, Lisa M / Pollack, Lois

Proceedings of the National Academy of Sciences of the United States of America

2017 Volume 114, Issue 2, Page(s) 334–339

Abstract: The nucleosome core particle (NCP) is the basic structural unit for genome packaging in eukaryotic cells and consists of DNA wound around a core of eight histone proteins. DNA access is modulated through dynamic processes of NCP disassembly. Partly ... ...

Abstract	The nucleosome core particle (NCP) is the basic structural unit for genome packaging in eukaryotic cells and consists of DNA wound around a core of eight histone proteins. DNA access is modulated through dynamic processes of NCP disassembly. Partly disassembled structures, such as the hexasome (containing six histones) and the tetrasome (four histones), are important for transcription regulation in vivo. However, the pathways for their formation have been difficult to characterize. We combine time-resolved (TR) small-angle X-ray scattering and TR-FRET to correlate changes in the DNA conformations with composition of the histone core during salt-induced disassembly of canonical NCPs. We find that H2A-H2B histone dimers are released sequentially, with the first dimer being released after the DNA has formed an asymmetrically unwrapped, teardrop-shape DNA structure. This finding suggests that the octasome-to-hexasome transition is guided by the asymmetric unwrapping of the DNA. The link between DNA structure and histone composition suggests a potential mechanism for the action of proteins that alter nucleosome configurations such as histone chaperones and chromatin remodeling complexes.
Language	English
Publishing date	2017-01-10
Publishing country	United States
Document type	Journal Article
ZDB-ID	209104-5
ISSN	1091-6490 ; 0027-8424
ISSN (online)	1091-6490
ISSN	0027-8424
DOI	10.1073/pnas.1611118114
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Article: Stability and folding mechanism of mesophilic, thermophilic and hyperthermophilic archael histones: the importance of folding intermediates.

Topping, Traci B / Gloss, Lisa M

Journal of molecular biology

2004 Volume 342, Issue 1, Page(s) 247–260

Abstract: The equilibrium stabilities to guanidinium chloride (GdmCl)-induced denaturation and kinetic folding mechanisms have been characterized for three archael histones: hFoB from the mesophile Methanobacterium formicicum; hMfB from the thermophile ... ...

Abstract	The equilibrium stabilities to guanidinium chloride (GdmCl)-induced denaturation and kinetic folding mechanisms have been characterized for three archael histones: hFoB from the mesophile Methanobacterium formicicum; hMfB from the thermophile Methanothermus fervidus; and hPyA1 from the hyperthermophile Pyrococcus strain GB-3a. These histones are homodimers of 67 to 69 residues per monomer. The equilibrium unfolding transitions, as measured by far-UV circular dichroism (CD) are highly reversible, two-state processes. The mesophilic hFoB is very unstable and requires approximately 1 M trimethyl-amine-N-oxide (TMAO) to completely populate the native state. The thermophilic histones are more stable, with deltaG degrees (H2O) values of 14 and 16 kcal mol(-1) for hMfB and hPyA1, respectively. The kinetic folding of hFoB and hPyA1 are two-state processes, with no detectable transient kinetic intermediates. For hMfB, there is significant development of CD signal in the stopped-flow dead time, indicative of the formation of a monomeric intermediate, which then folds/associates in a single, second-order step to form the native dimer. While the equilibrium stability to chemical denaturation correlates very well with host growth temperature, there is no simple relationship between folding rates and stability for the archael histones. In the absence of denaturant, the log of the unfolding rates correlate with equilibrium stability. The folding/association of the moderately stable hMfB is the most rapid, with a rate constant in the absence of GdmCl of 3 x 10(6) M(-1) s(-1), compared to 9 x 10(5) M(-1) s(-1) for the more stable hPyA1. It appears that the formation of the hMfB burst-phase monomeric ensemble serves to enhance folding efficiency, rather than act as a kinetic trap. The folding mechanism of the archael histones is compared to the folding of other intertwined, segment-swapped, alpha-helical, DNA-binding dimers (ISSADD), including the eukaryotic heterodimeric histones, which fold more rapidly. The importance of monomeric and dimeric kinetic intermediates in accelerating ISSADD folding reactions is discussed.
MeSH term(s)	Archaeal Proteins/chemistry ; Archaeal Proteins/genetics ; Guanidine/chemistry ; Histones/chemistry ; Histones/genetics ; Protein Denaturation ; Protein Folding ; Protein Structure, Secondary ; Thermodynamics
Chemical Substances	Archaeal Proteins ; Histones ; Guanidine (JU58VJ6Y3B)
Language	English
Publishing date	2004-09-03
Publishing country	England
Document type	Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
ZDB-ID	80229-3
ISSN	1089-8638 ; 0022-2836
ISSN (online)	1089-8638
ISSN	0022-2836
DOI	10.1016/j.jmb.2004.07.045
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In stock of ZB MED Cologne/Königswinter

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In stock of ZB MED Cologne/Königswinter

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In stock of ZB MED Cologne/Königswinter

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Full text online

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In stock of ZB MED Cologne/Königswinter

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