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LRGUK-1 is required for basal body and manchette function during spermatogenesis and male fertility.

Liu Y, DeBoer K, de Kretser DM, O'Donnell L, O'Connor AE, Merriner DJ, Okuda H, Whittle B, Jans DA, Efthymiadis A, McLachlan RI, Ormandy CJ, Goodnow CC, Jamsai D, O'Bryan MK - PLoS Genet. (2015)

Bottom Line: Specifically, LRGUK-1 is required for basal body attachment to the plasma membrane, the appropriate formation of the sub-distal appendages, the extension of axoneme microtubules and for microtubule movement and organisation within the manchette.Several of these functions may be achieved in association with the LRGUK-1 binding partner HOOK2.Collectively, these data establish LRGUK-1 as a major determinant of microtubule structure within the male germ line.

View Article: PubMed Central - PubMed

Affiliation: Department of Anatomy and Developmental Biology, School of Biomedical Sciences, Monash University, Australia.

ABSTRACT
Male infertility affects at least 5% of reproductive age males. The most common pathology is a complex presentation of decreased sperm output and abnormal sperm shape and motility referred to as oligoasthenoteratospermia (OAT). For the majority of OAT men a precise diagnosis cannot be provided. Here we demonstrate that leucine-rich repeats and guanylate kinase-domain containing isoform 1 (LRGUK-1) is required for multiple aspects of sperm assembly, including acrosome attachment, sperm head shaping and the initiation of the axoneme growth to form the core of the sperm tail. Specifically, LRGUK-1 is required for basal body attachment to the plasma membrane, the appropriate formation of the sub-distal appendages, the extension of axoneme microtubules and for microtubule movement and organisation within the manchette. Manchette dysfunction leads to abnormal sperm head shaping. Several of these functions may be achieved in association with the LRGUK-1 binding partner HOOK2. Collectively, these data establish LRGUK-1 as a major determinant of microtubule structure within the male germ line.

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Axoneme defects in LrgukKaos/Kaos mice.(A) The staining of testis sections with the axoneme marker, acetylated tubulin, indicated an almost complete absence of axoneme development in LrgukKaos/Kaos germ cells. (B) Transmission electron microscopy indicating the absence of axoneme development in wild type and LrgukKaos/Kaos elongating spermatids. Red arrows indicate outer dense fibers. Scale bar = 0.2 μm. (C-D) Transmission electron microscopy of basal body docking to the plasma and nuclear membrane (C) and subsequent axoneme extension in LrgukWT/WT cells but the absence of plasma membrane attachment and axoneme of extension in LrgukKaos/Kaos spermatids. Scale bar = 2 μm. (E) A closer examination of the early phases of basal body structure and movement revealed the presence of normal distal appendages (DAPs, green arrow)) and sub-distal appendages (SAPs, red arrow) in wild type cells associated with plasma membrane attachment. LrgukKaos/Kaos germ cells contained enlarged SAP and the basal body failed to associate with the plasma membrane. The scale bar = 2μm.
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pgen.1005090.g007: Axoneme defects in LrgukKaos/Kaos mice.(A) The staining of testis sections with the axoneme marker, acetylated tubulin, indicated an almost complete absence of axoneme development in LrgukKaos/Kaos germ cells. (B) Transmission electron microscopy indicating the absence of axoneme development in wild type and LrgukKaos/Kaos elongating spermatids. Red arrows indicate outer dense fibers. Scale bar = 0.2 μm. (C-D) Transmission electron microscopy of basal body docking to the plasma and nuclear membrane (C) and subsequent axoneme extension in LrgukWT/WT cells but the absence of plasma membrane attachment and axoneme of extension in LrgukKaos/Kaos spermatids. Scale bar = 2 μm. (E) A closer examination of the early phases of basal body structure and movement revealed the presence of normal distal appendages (DAPs, green arrow)) and sub-distal appendages (SAPs, red arrow) in wild type cells associated with plasma membrane attachment. LrgukKaos/Kaos germ cells contained enlarged SAP and the basal body failed to associate with the plasma membrane. The scale bar = 2μm.

Mentions: The LrgukKaos/Kaos sperm phenotype has some similarities with that observed for HOOK2 depleted retinal cells, suggesting they lie in a common pathway. Greatly reduced axoneme development was evidenced in testis sections stained for the axoneme marker acetylated tubulin and the absence of 9+2 axoneme structure was seen at the electron microscopic level (Fig. 7A-E). An analysis of the early steps of centriole/basal body movement and axoneme development, however, revealed abnormalities in LrgukKaos/Kaos germ cells, strongly suggestive of a critical role for LRGUK-1 beyond that currently documented for HOOK2, specifically in the formation of the centriole appendages. In early wild type spermatids the mature centriole can be distinguished from the adjacent daughter centriole by the possession of accessory structures known as the sub-distal appendages (SAP) and distal appendages (DAPs) [30]. The mature centriole then migrates to the spermatid periphery and attaches to the plasma membrane before attaching to the nuclear pole opposite the acrosome [16]. Recent data has shown the DAPs are required for basal body-to-membrane docking [31], and SAPs are believed to be where axoneme microtubules are anchored and are thus required for axoneme extension [32–34]. Electron microscopy of spermatids from LrgukWT/WT spermatids clearly showed the docking of mature centrioles to the plasma membrane and the associated DAPs and SAPs (Fig. 7E). In contrast, the over-whelming majority of basal bodies in spermatids from LrgukKaos/Kaos mice contained SAPs that were overtly enlarged and plasma membrane attachments were very infrequent (<1% of the time) (Fig. 7E). Consistent with abnormal SAP function, microtubule extension from the LrgukKaos/Kaos basal body into an axoneme was extremely rare (Fig. 7D). Despite the absence of membrane attachment basal bodies did contain DAP-like structures. LrgukKaos/Kaos basal bodies did, however, appeared to attach to the nuclear membrane normally (Fig. 7E). In comparison to the basal body phenotype seen in LrgukKaos/Kaos spermatids, the loss of HOOK2 function during retinal cell primary cilia formation had no reported effect on SAP formation [19]. These data suggest that LRGUK-1 is required for the formation / function of the DAPs and SAPs in spermatids. Currently it is unknown if these effects are independent of HOOK2 or if they are spermatid-specific functions and thus, not seen following HOOK2 knockdown in retinal cells.


LRGUK-1 is required for basal body and manchette function during spermatogenesis and male fertility.

Liu Y, DeBoer K, de Kretser DM, O'Donnell L, O'Connor AE, Merriner DJ, Okuda H, Whittle B, Jans DA, Efthymiadis A, McLachlan RI, Ormandy CJ, Goodnow CC, Jamsai D, O'Bryan MK - PLoS Genet. (2015)

Axoneme defects in LrgukKaos/Kaos mice.(A) The staining of testis sections with the axoneme marker, acetylated tubulin, indicated an almost complete absence of axoneme development in LrgukKaos/Kaos germ cells. (B) Transmission electron microscopy indicating the absence of axoneme development in wild type and LrgukKaos/Kaos elongating spermatids. Red arrows indicate outer dense fibers. Scale bar = 0.2 μm. (C-D) Transmission electron microscopy of basal body docking to the plasma and nuclear membrane (C) and subsequent axoneme extension in LrgukWT/WT cells but the absence of plasma membrane attachment and axoneme of extension in LrgukKaos/Kaos spermatids. Scale bar = 2 μm. (E) A closer examination of the early phases of basal body structure and movement revealed the presence of normal distal appendages (DAPs, green arrow)) and sub-distal appendages (SAPs, red arrow) in wild type cells associated with plasma membrane attachment. LrgukKaos/Kaos germ cells contained enlarged SAP and the basal body failed to associate with the plasma membrane. The scale bar = 2μm.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4363142&req=5

pgen.1005090.g007: Axoneme defects in LrgukKaos/Kaos mice.(A) The staining of testis sections with the axoneme marker, acetylated tubulin, indicated an almost complete absence of axoneme development in LrgukKaos/Kaos germ cells. (B) Transmission electron microscopy indicating the absence of axoneme development in wild type and LrgukKaos/Kaos elongating spermatids. Red arrows indicate outer dense fibers. Scale bar = 0.2 μm. (C-D) Transmission electron microscopy of basal body docking to the plasma and nuclear membrane (C) and subsequent axoneme extension in LrgukWT/WT cells but the absence of plasma membrane attachment and axoneme of extension in LrgukKaos/Kaos spermatids. Scale bar = 2 μm. (E) A closer examination of the early phases of basal body structure and movement revealed the presence of normal distal appendages (DAPs, green arrow)) and sub-distal appendages (SAPs, red arrow) in wild type cells associated with plasma membrane attachment. LrgukKaos/Kaos germ cells contained enlarged SAP and the basal body failed to associate with the plasma membrane. The scale bar = 2μm.
Mentions: The LrgukKaos/Kaos sperm phenotype has some similarities with that observed for HOOK2 depleted retinal cells, suggesting they lie in a common pathway. Greatly reduced axoneme development was evidenced in testis sections stained for the axoneme marker acetylated tubulin and the absence of 9+2 axoneme structure was seen at the electron microscopic level (Fig. 7A-E). An analysis of the early steps of centriole/basal body movement and axoneme development, however, revealed abnormalities in LrgukKaos/Kaos germ cells, strongly suggestive of a critical role for LRGUK-1 beyond that currently documented for HOOK2, specifically in the formation of the centriole appendages. In early wild type spermatids the mature centriole can be distinguished from the adjacent daughter centriole by the possession of accessory structures known as the sub-distal appendages (SAP) and distal appendages (DAPs) [30]. The mature centriole then migrates to the spermatid periphery and attaches to the plasma membrane before attaching to the nuclear pole opposite the acrosome [16]. Recent data has shown the DAPs are required for basal body-to-membrane docking [31], and SAPs are believed to be where axoneme microtubules are anchored and are thus required for axoneme extension [32–34]. Electron microscopy of spermatids from LrgukWT/WT spermatids clearly showed the docking of mature centrioles to the plasma membrane and the associated DAPs and SAPs (Fig. 7E). In contrast, the over-whelming majority of basal bodies in spermatids from LrgukKaos/Kaos mice contained SAPs that were overtly enlarged and plasma membrane attachments were very infrequent (<1% of the time) (Fig. 7E). Consistent with abnormal SAP function, microtubule extension from the LrgukKaos/Kaos basal body into an axoneme was extremely rare (Fig. 7D). Despite the absence of membrane attachment basal bodies did contain DAP-like structures. LrgukKaos/Kaos basal bodies did, however, appeared to attach to the nuclear membrane normally (Fig. 7E). In comparison to the basal body phenotype seen in LrgukKaos/Kaos spermatids, the loss of HOOK2 function during retinal cell primary cilia formation had no reported effect on SAP formation [19]. These data suggest that LRGUK-1 is required for the formation / function of the DAPs and SAPs in spermatids. Currently it is unknown if these effects are independent of HOOK2 or if they are spermatid-specific functions and thus, not seen following HOOK2 knockdown in retinal cells.

Bottom Line: Specifically, LRGUK-1 is required for basal body attachment to the plasma membrane, the appropriate formation of the sub-distal appendages, the extension of axoneme microtubules and for microtubule movement and organisation within the manchette.Several of these functions may be achieved in association with the LRGUK-1 binding partner HOOK2.Collectively, these data establish LRGUK-1 as a major determinant of microtubule structure within the male germ line.

View Article: PubMed Central - PubMed

Affiliation: Department of Anatomy and Developmental Biology, School of Biomedical Sciences, Monash University, Australia.

ABSTRACT
Male infertility affects at least 5% of reproductive age males. The most common pathology is a complex presentation of decreased sperm output and abnormal sperm shape and motility referred to as oligoasthenoteratospermia (OAT). For the majority of OAT men a precise diagnosis cannot be provided. Here we demonstrate that leucine-rich repeats and guanylate kinase-domain containing isoform 1 (LRGUK-1) is required for multiple aspects of sperm assembly, including acrosome attachment, sperm head shaping and the initiation of the axoneme growth to form the core of the sperm tail. Specifically, LRGUK-1 is required for basal body attachment to the plasma membrane, the appropriate formation of the sub-distal appendages, the extension of axoneme microtubules and for microtubule movement and organisation within the manchette. Manchette dysfunction leads to abnormal sperm head shaping. Several of these functions may be achieved in association with the LRGUK-1 binding partner HOOK2. Collectively, these data establish LRGUK-1 as a major determinant of microtubule structure within the male germ line.

Show MeSH
Related in: MedlinePlus